Illinois 2 used to follow the Rock River from
Rock Island to
South Beloit. It was used in the 19th century as a primary trading route from
Rockford to Rock Island, The
Rock River was not used as a trading route for boats as it is only navigable west of
Rock Falls. Illinois 2 has since been superseded by
Interstate 39 and
Interstate 88 for most ground transportation, but the original route remains. In Sterling, IL 2 begins as a one-way pair. Near the
Sinnissippi Mounds, the two one-way roads merge into a two-way road. From Sterling to
Dixon, IL 2 largely follows a portion of
Lincoln Highway but with one exception. Lincoln Highway branches off northeast to
Palmyra and then back southeast to IL 2 just northwest of Dixon. Just north of Dixon, both routes run concurrently with US 52 and IL 26. They then cross the Rock River to get to downtown. In downtown, IL 2 branches off northeast from the other two routes. At Grand Detour, IL 2 transitions from following the south/east bank of Rock River to the north/west bank via a bridge. Further north, it passes through
Castle Rock State Park, IL 64 at the
Ogle County Courthouse in Oregon, and IL 72 in Byron (runs concurrently with IL 2). North of the
Chicago Rockford International Airport, IL 2 turns north. At this point, it largely parallels IL 251 for the rest of the route which is east of the river. It then meets US 20 at a diamond interchange (formerly a cloverleaf interchange). As IL 2 gets closer to downtown Rockford, another split occurs. Northbound traffic continues on Main Street, then east on Chestnut Street (US 20 Business), then north on Wyman Street, then west on Park Avenue near the site of
Beattie Park Mound Group, and then back north on Main Street before merging. Southbound traffic has to turn west onto John Street, then south on Church Street, and then east on Cedar Street before merging. In Rockton, IL 2 transitions from the west side of the river to the east side again. Further north, IL 75 runs concurrently with IL 2 from Rockton to South Beloit. One third of a mile from the Wisconsin state line, IL 75 leaves this concurrency to travel East while IL 2 continues North over a railroad grade crossing and Turtle Creek before reaching its Northern terminus at a junction with
WIS 213. == History ==