Illinois to Valparaiso SR 2 begins at the Illinois–Indiana State Line where Illinois Route 17 ends. SR 2 heads northeast toward
U.S. Route 41 (US 41) and is concurrent with US 41 for . It then heads east toward
Lowell; beyond Lowell there is a short concurrency with
State Road 55 (SR 55), followed by an
interchange with
Interstate 65 (I-65) at exit number 240. About to the east, SR 2 joins
U.S. Route 231 (US 231) and they are concurrent for . After SR 2 leaves US 231 it heads north-northeast toward Valparaiso.
Valparaiso to LaPorte SR 2 enters Valparaiso from the southwest and joins
U.S. Route 30 (US 30). At the
State Road 49 (SR 49) exit, SR 2 joins SR 49 north. Soon after SR 2 leaves SR 49 and heads northeast toward
LaPorte. Passing through
Westville, there is a short concurrency with
U.S. Route 421 (US 421).
LaPorte to South Bend SR 2 enters LaPorte from the west along with
State Road 39 (SR 39). In downtown LaPorte SR 2 has an
intersection with
U.S. Route 35 (US 35); here, SR 39 is concurrent with US 35. From this point, SR 2 is a four-lane divided highway. SR 2 heads northeast from LaPorte to
Rolling Prairie where it meets US 20. Here, US 20 and SR 2 switch alignments at a roundabout interchange; US 20 follows the north and west legs of the interchange, while SR 2 follows the south and east legs. On the west side of South Bend, SR 2 ends at an interchange with US 20 and
U.S. Route 31 (US 31). == History ==