Interstate 70 in Maryland

I-70 has several official designations along its course through Maryland. The Interstate Highway is designated Eisenhower Memorial Highway from the Pennsylvania state line east to I-270 in Frederick. The highway received this designation from a 1973 act of Congress commemorating the route of the 1919 U.S. Army convoy from Washington, D.C., to San Francisco, California, in which President Dwight D. Eisenhower participated, an ordeal that served as one of his inspirations for the Interstate Highway System. All of I-70 in Frederick County was designated the Korean War Veterans Memorial Highway by the Maryland General Assembly in 2002. Large stone markers featuring reliefs of the Korean Peninsula were erected in the median of I-70 in Myersville and Mount Airy in 2004. Along its concurrency with US 40 from I-270 in Frederick to east of West Friendship, I-70 is known as Baltimore National Pike. The Interstate is unnamed from US 40 near West Friendship to its eastern terminus in Baltimore. Like all mainline Interstates, I-70 is a part of the National Highway System for its entire length. Hancock to Hagerstown I-70 enters Washington County concurrent with US 522 from Fulton County, Pennsylvania, north of the town of Hancock. Just south of the state line, the four-lane freeway has a full Y interchange with I-68 and US 40, which head west toward Cumberland as the National Freeway. US 40 begins to run concurrently with I-70 just as US 522 leaves I-70 at another full Y interchange through which I-70 curves to the east. US 522 heads south, providing access to downtown Hancock before crossing the Potomac River into West Virginia. I-70 heads east and gains a lane in each direction to climb a ridge that separates the interchanges from the valley of Tonoloway Creek. The third lane eastbound ends at the top of the ridge and the third lane westbound begins just west of the Interstate's partial interchange with Maryland Route 144 (MD 144; Main Street), which lacks a ramp from MD 144 to westbound I-70. East of MD 144, I-70 parallels the Western Maryland Rail Trail, Chesapeake and Ohio Canal, and Potomac River while heading east along a narrow corridor between the river and several north–south ridges. Within this corridor, the freeway has a pair of partial interchanges with MD 615 (Millstone Road). West of Indian Springs, the valley opens up, and US 40 leaves the Interstate at a partial interchange just west of Licking Creek. I-70 continues to parallel the canal and rail trail at a distance until its diamond interchange with MD 56 (Big Pool Road) at Big Pool, where the freeway curves away from the Potomac River and passes to the south of Stone Quarry Ridge and Boyd Mountain. Just south of Clear Spring, I-70 crosses Toms Run within its diamond interchange with MD 68 (Clear Spring Road). Signs on westbound I-70 prior to the MD 68 interchange remind motorists they should remain on I-70 to access I-68. The westbound rest area is where the DC snipers, John Allen Muhammad and Lee Boyd Malvo, were apprehended by police in October 2002. I-70's eastbound climbing lane disappears and the Interstate has a westbound climbing lane from the top of the mountain southeast to a diamond interchange with MD 17 (Myersville Middletown Road) south of Myersville, where the freeway enters Middletown Valley. Within the valley, the Interstate crosses Catoctin and Little Catoctin creeks. I-70 gains an eastbound climbing lane as it climbs Braddock Mountain, on top of which the freeway passes under a concrete arch bridge carrying Ridge Road. Westbound I-70 has a climbing lane as the highway descends Braddock Mountain and has partial interchanges with US 40 (National Pike) and US 40 Alt. (Old National Pike). The first interchange is a pair of flyover ramps from eastbound I-70 to eastbound US 40 and from westbound US 40 to westbound I-70. The second interchange is a half diamond interchange with an exit ramp from westbound I-70 to US 40 Alt. and an entrance ramp to eastbound I-70. Woodlawn to Baltimore I-70 officially ends at I-695. The extension beyond I-695 to the I-70 park-and-ride facility was formally dropped from the Interstate Highway System in August 2014 after approvals from the American Association of State Highway and Transportation Officials (AASHTO) This stub is now designated Maryland Route 570 (MD 570) but remains signed as I-70. West of the I-695 interchange, I-70 has an average traffic value of 94,221 vehicles. East of the interchange, MD 570 continues as a four-lane highway for local traffic that averages 25,300 vehicles per day. The highway's speed limit reduces to and then as it passes through its final interchange, a partial cloverleaf junction with MD 122 (Security Boulevard), which continues southeast into Baltimore as Cooks Lane. Just east of the MD 122 interchange, MD 570 enters the city of Baltimore and the freeway's median expands into a park-and-ride facility that is accessed at the highways's eastern terminus at a U-turn adjacent to Gwynns Falls/Leakin Park. Eastbound MD 570 traffic that wishes to access Cooks Lane has to make a U-turn at the terminus and exit from a westbound loop ramp. Westbound access to MD 570 is done via a single entrance ramp off Ingleside Avenue, which is considered part of the MD 122 interchange. The very short section of MD 570 in the city of Baltimore is maintained by the Baltimore City Department of Transportation instead of the Maryland State Highway Administration (MDSHA). ==History==

I-70 was planned to follow the US 40 corridor from Hancock east to Frederick, where the Interstate Highway designation split. I-70N would continue following US 40 east to Baltimore while I-70S would follow US 240 southeast toward Washington. In 1974, the suffixed designations were eliminated; I-70N became an eastward extension of I-70 while I-70S was designated I-270. Baltimore National Pike and Frederick Freeway The first section of I-70 in Maryland was constructed as Baltimore National Pike, a four-lane divided highway relocation and reconstruction of US 40 from the Pine Orchard community west of Ellicott City west to the east end of Patrick Street in Frederick. US 40 was constructed from Pine Orchard to MD 32 in West Friendship between 1949 and 1951. An overpass of MD 32 and two-way ramp connection between the two highways were constructed in 1951 and 1952. An overpass and connecting ramp were also constructed at MD 97, which was included in the portion of US 40 constructed from West Friendship to Morgan Station Road west of Cooksville between 1950 and 1952. The third section of Baltimore National Pike was built from Morgan Station Road into Carroll County just west of the Patapsco River in 1952 and 1953. The next section of relocated US 40, from west of the Patapsco River through the Ridgeville section of Mount Airy into Frederick County west of MD 27, broke ground in 1953 and was completed by 1955. An interchange with MD 27 in Ridgeville was constructed in 1953 and 1954. The final section of Baltimore National Pike, from east of the Monocacy River to the east end of Patrick Street near modern exit 56, was expanded to a divided highway in 1953 with the exception of the Monocacy River crossing. Engineering work on a second bridge across the Monocacy River began in 1954. The western end of Baltimore National Pike was planned to tie into both Patrick Street and the eastern end of the Frederick Freeway, which would serve as a US 40 freeway bypass of downtown Frederick between its two interchanges with Patrick Street. Construction on the east–west US 40 portion of the Frederick Freeway began in 1954 and was completed by 1958. Old US 40 through downtown Frederick later became part of MD 144. The freeway's original interchanges along what is now I-70 included a partial interchange with Patrick Street east of Frederick, the present interchange at South Street, folded diamond interchanges at MD 355 and New Design Road, and a partial interchange with Washington National Pike (now I-270), where the Frederick Freeway curved north to cloverleaf interchanges with US 340 and the western end of Patrick Street. The Frederick Freeway was marked with exit numbers in 1963; the portion that is part of I-70 started from exit 1 at MD 144 east of Frederick and went to exit 4 at New Design Road. Interstate construction and upgrades The next section of US 40 and future I-70 to be upgraded was east of Hancock. US 40 was reconstructed as a divided highway from Tonoloway Creek at the eastern end of Hancock parallel to the Potomac River to the community of Millstone at what is now the southern terminus of MD 615 in 1961. This piece of highway became the first completed section of highway in Maryland to be marked as I-70 in 1962. In 1964, construction began on I-70 from the western end of the existing highway to the Pennsylvania state line. This project happened concurrently with the construction of what is now I-68 west from I-70 to MD 144 west of Hancock; both projects were completed in 1966. Construction of I-70 from Hancock to Frederick was fully underway in an eastward direction by 1965. The Interstate opened from MD 615 to MD 56 in 1965; from I-81 to US 40 east of Hagerstown in 1968; and from US 40 to the Frederick Freeway in 1969. When the interchange between the Frederick Freeway and Washington National Pike was reconstructed to add I-70 toward Hagerstown in 1969, the freeway's interchange with New Design Road was removed. Exit numbers were added east of Frederick in 1978; these exit numbers, however, were each 2 less than the present numbers, which were marked in 1983. I-70 was relocated away from the original alignment of US 40 between its junctions with MD 144 in Frederick and Bartonsville around 1987; the old highway became an eastern extension of MD 144. Outside of the reconstruction of the Interstate through Frederick beginning in the 1990s, there have been two interchanges revised or added, both near Hagerstown. A direct ramp was added from eastbound I-70 to southbound MD 65 in 1995; this interchange had four ramps, including two loop ramps with eastbound I-70, from at least 1968. I-70's interchange with MD 632 opened in 1999. In Washington County, MDSHA reconstructed and widened I-70's bridges over Conococheague Creek starting in mid-2012. The reconstruction of the bridges was completed in July 2014. In Frederick County, the partial interchange between I 70 and MD 144 in Bartonsville was reconfigured to a full interchange. An exit ramp from Meadow Road to westbound I-70 was completed in October 2019. MD 144 was reconfigured and widened to four lanes from Baltimore Road to just east of Meadow Road in August 2022, and an entry ramp was completed from eastbound I-70 to MD 144. Meadow Road was widened to four lanes from MD 144 to the intersection with westbound I-70 at the same time. Reconstruction through Frederick In 1984, MDSHA completed the I-70 Corridor Planning Study, which examined the segment of I-70 from the Mount Philip Road overpass between Braddock Mountain and Frederick to just east of MD 144 at the western end of the project underway to relocate the Interstate through Bartonsville. The study proposed a series of projects to upgrade I-70 through Frederick, much of which had been constructed as the Frederick Freeway in the late 1950s, to Interstate standards. The four-lane freeway was plagued with closely spaced interchanges with substandard acceleration and deceleration lanes and curve radiuses. Many of the interchanges were missing important movements between highways. For instance, travelers aiming to move from southbound US 15 to westbound I-70 needed to use US 40 through Frederick's heavily commercialized Golden Mile to join I-70 at exit 48. The second project filled in a pair of missing connections to the I-70/I-270 interchange last updated in 1969. The third project was the replacement of I-70's interchange with MD 355, a four-ramp partial cloverleaf interchange constructed in 1956. In 2005, as part of a related project, the MD 85/MD 355 intersection was reconstructed and MD 85 was extended to a temporary terminus east of MD 355 at a pair of ramps with eastbound I-70. Eastbound I-70's existing ramps at MD 355 were closed. The fourth project to upgrade I-70 through Frederick, which will upgrade the interchanges at South Street and MD 144 built in 1956, began in late 2010. Eastbound I-70's ramps with Reichs Ford Road, which leads to South Street, will be reconstructed. The westbound ramps serving South Street will be removed. The missing movements on the eastern end of Frederick will be provided by reconstruction of westbound I-70's ramps with MD 144. A ramp from MD 144 to westbound I-70 will be added; both that ramp and the exit ramp from westbound I-70 will meet MD 144 at a roundabout. Once the interchanges are reconstructed, I-70 will be expanded to six lanes from east of MD 144 to I-270. The fifth and final project to upgrade I-70 through Frederick will expand I-70 to six lanes between Mount Philip Road and I-270. ==Future==

In Howard County, as part of the upgrade of MD 32 to a freeway from MD 108 to I-70, the state highway's junction with I-70 will be reconstructed from a diamond interchange to a partial cloverleaf design that will allow free-flowing traffic from both directions of MD 32 onto I-70. In Howard County, a study is underway concerning improvements to the portion of I-70 between MD 32 and US 29; between the US 40 split and US 29, I-70 is only four lanes. The study will look at widening the Interstate to six or eight lanes as well as possible improvements on US 29 and Marriottsville Road at their respective interchanges with I-70. In Baltimore and Howard counties, a study is underway in consideration of widening I-70 between I-695 and US 29 to eight or possibly 10 lanes. This would require the reconstruction of the bridges over the Patapsco River in both directions in order to accommodate more lanes. A proposal has been made to replace the interchange at I-695 with the goal of improving mobility and reducing congestion and delays. The interchange, built in the 1960s, currently handles significantly more traffic than it was originally designed for, resulting in frequent traffic congestion in the area. The proposal, named Triple Bridges, is currently in the planning phase, and is scheduled to start the design–build phase in 2027. ==Highway in Baltimore==

Early freeway plans for Baltimore Nine plans for a Baltimore city freeway system were put together by Baltimore city planners between 1942 and 1957. The most influential of these plans was portrayed in the Smith Report of 1945, which heavily influenced future proposals, including the proposal that would be included in the General Location of National System of Interstate Highways, also known as the Yellow Book, in 1955. None of the plans gained traction due to either decision makers figuring the freeways were not needed or opposition to the east–west freeway passing straight through the central business district (CBD) or immediately to the north of the CBD. By the late 1950s, however, Baltimore was starting to suffer from the flight of its commercial and industrial concerns and residents to the suburbs in response to the easy access provided by the developing Baltimore Beltway. The route of the East–West Expressway in the 10-D System would require condemning a greater number of properties compared to Darling's plan due to I-70N and I-95 passing through several residential neighborhoods south of the CBD. Several of the civic groups with which Darling had compromised opposed Expressway Consultants's uncompromising position toward their route through Leakin Park. Many of the civic groups, however, still opposed I-70 passing through Gwynns Falls/Leakin Park; the groups used litigation and political will to indefinitely delay the construction of I-70 through the park. Route description of I-70 in the 3-A System Had I-70 been constructed as planned in the 3-A System, I-70 would have continued east from its former terminus at the Baltimore city limits near Security Boulevard. The Interstate would curve to the northeast and traverse Dead Run and Franklintown Road, then pass through a short tunnel underneath a hill in Leakin Park. I-70 would curve east through Gwynns Falls Park, where the freeway would cross over Dead Run and Franklintown Road again just south of the stream's confluence with Gwynns Falls. The Interstate would parallel Gwynns Falls southeast to an interchange with Hilton Parkway, a four-lane divided highway that connects the portions of Hilton Street on either side of the Gwynns Falls valley. The directional T interchange would provide access from both directions of I-70 to northbound Hilton Parkway and from southbound Hilton Parkway to I-70. I-70 would continue south while paralleling Hilton Parkway on the east until the freeway's underpass of US 40 (Edmondson Avenue). I-70 would have continued southeast along Gwynns Falls and what is now CSX Transportation's Hanover Subdivision. The Interstate would have met the western end of I-170 at a directional T interchange where Baltimore Street and Amtrak's Northeast Corridor cross over Gwynns Falls. I-170 would have headed northeast closely paralleling the Amtrak Northeast Corridor before veering east at West Baltimore station on MARC Train's Penn Line to join the constructed portion of I-170, which is now part of US 40. I-70 would have continued southeast to a partial interchange with MD 144 (Frederick Avenue) that would have allowed access to and from the direction of I-95. The Interstate would have passed under US 1 (Wilkens Avenue) before reaching its terminus at I-95. I-70's junction with I-95 would have been a directional T interchange constructed over a rail yard on the Mount Clare Branch of CSX Transportation's Baltimore Terminal Subdivision. When I-95 was completed from Caton Avenue to Russell Street in February 1978, the highway was paralleled by extended ramps east from the Caton Avenue interchange that would have allowed connections between I-70 and Caton Avenue (US 1 Alt.) and segregated I-70 and Caton Avenue traffic from the partial interchange with Washington Boulevard just to the east. ==Exit list==

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I-70 has two auxiliary Interstate Highways in Maryland. Interstate 270 Interstate 270 (I-270) is a auxiliary Interstate Highway in the U.S. state of Maryland that travels between I-495 (Capital Beltway) just north of Bethesda in Montgomery County and I-70/US 40 in the city of Frederick in Frederick County. It consists of the mainline as well as a spur that provides access to and from southbound I-495. I-270 is known as the Dwight D. Eisenhower Memorial Highway as well as the Washington National Pike. Most of the southern part of the route in Montgomery County passes through suburban areas around Rockville and Gaithersburg that are home to many biotech firms. This portion of I-270 is up to 12 lanes wide and consists of a local–express lane configuration as well as HOV lanes that are in operation during peak travel times. North of the Gaithersburg area, the road continues through the northern part of Montgomery County, passing Germantown and Clarksburg as a six- to eight-lane highway with an HOV lane in the northbound direction only. North of here, I-270 continues through rural areas into Frederick County and toward the city of Frederick as a four-lane freeway. MD 200 east of I-370 to MD 28 (Norbeck Road) opened on February 23, 2011, resulting in the truncation of I-370 to the interchange with MD 200 and the redesignation of the road leading into the Shady Grove Metro station as MD 200A. ==See also==