The Monon Trail is a rail trail in Indiana. It uses a portion of the Chicago-Indianapolis main line of the former Monon Railroad, which was abandoned between Indianapolis and Delphi, Indiana in 1987. The trail serves both bicyclists and pedestrians. It runs from Indianapolis (passing through the Mapleton-Fall Creek, Meridian-Kessler, and Broad Ripple neighborhoods) into Carmel and Westfield, Indiana, a length of 16.7 miles (26.9 km).
The 10.0 miles (16.1 km) of in Indianapolis were completed in 1999 and the 5.2 miles (8.4 km) in Carmel were opened between 2001 and 2002. The trail was extended 1.5 miles (2.4 km) into Westfield in the fall of 2008. In the City of Westfield, the trail has been extended north over the abandoned Monon right of way toward Sheridan, Indiana. The Monon is used by more than 4,000 people each day. The trail cost about $5.5 million to create.