The entirety of the Lake Ontario State Parkway mainline is designated as NY 947A, while the connector between the parkway and
NY 18 in
Lakeside Beach State Park—named Lakeside Beach Road—is designated as NY 948A. Both are
reference route designations and are thus
unsigned.
Orleans County and Hamlin Beach The Lake Ontario State Parkway begins at an interchange with Lakeside Beach Road in Lakeside Beach State Park, located within the town of
Carlton in north-central
Orleans County. It heads eastward as a four-lane
freeway as part of the
Seaway Trail, which enters the area from the west on NY 18 and turns north onto Lakeside Beach Road to access the parkway. The four-lane parkway exits the park and enters an area dominated by open, cultivated fields, where it skirts the southern edge of
Oak Orchard State Marine Park, a small park situated at the mouth of the
Oak Orchard River. Not far to the east, the parkway crosses the river itself and connects to the northern terminus of
NY 98 by way of an interchange.) and
NY 19—to the parkway and Hamlin Beach State Park. East of the park, the parkway comes close to the lake shore once again; however, most of the route in Hamlin is separated from the lake by a series of linear, lakeside hamlets. Roughly east of Hamlin Beach, the highway becomes a four-lane
expressway ahead of a four-way intersection with
NY 19.
Hamlin to Rochester Past NY 19, the parkway crosses over Sandy Creek and heads into a portion of Hamlin with less open fields and more forested areas. It has intersections with three more roads—including
NY 260—before passing into Parma at a junction with Hamlin–Parma Town Line Road. Junctions with
NY 259 and two more local roads come next, followed by the last of the eight at-grade intersections: Payne Beach Road on the Parma–
Greece town line. In Greece, the parkway takes a more southeasterly routing, matching the curvature of Lake Ontario's shoreline. About into Greece, the parkway becomes a four-lane
freeway ahead of an interchange with
NY 261. At this point, the trees that had surrounded the parkway begin to dwindle in number, once again opening up views of the lake. At NY 261, the parkway briefly turns southward, crossing over Salmon Creek and passing west of
Braddock Bay before resuming a southeasterly alignment at the East Manitou Road interchange. Here, the Lake Ontario Parkway connects to
Braddock Bay State Park, located just northeast of the exit. The parkway leaves the lake for good after the East Manitou Road junction, staying roughly from the lake shore for the remainder of its routing. As it proceeds onward, it runs along the southwestern side of Long Pond and subsequently meets Long Pond Road. Here, the surroundings of the parkway begin to change, becoming more developed as homes gradually overtake the forests and fields that had surrounded the parkway since Carlton. The parkway winds its way southeastward, passing by homes to the south and marshlands surrounding
Beatty Point to the north. At the eastern edge of the marsh, the Lake Ontario Parkway meets the northern end of the controlled-access
NY 390. From here eastward, the parkway travels through highly populated areas of the town, meeting Dewey Avenue, Greenleaf Road, and Latta Road and passing under the
Hojack Line. East of Latta Road, it passes into the city of
Rochester and its
Charlotte neighborhood, where it terminates just later at an intersection with Lake Avenue. The right-of-way of the parkway and the Seaway Trail both continue eastward as Pattonwood Drive, which leads to the
Colonel Patrick O'Rorke Memorial Bridge a short distance to the east. Two blocks north of the junction is the
National Register of Historic Places-listed
Charlotte–Genesee Lighthouse, located off Lake Avenue. ==History==