INDIANAPOLIS (AP) — Proposals have been made to extend an Indiana rail line.

The Indianapolis Star reports four proposals were submitted this week to the Hoosier Heritage Port Authority for expanded service along the Nickel Plate rail line. The 37-mile line runs through Marion and Hamilton counties.

Three proposals suggest running trains from Tipton to downtown Indianapolis. Those plans come from the Indianapolis Transportation Museum, the Indianapolis Metropolitan Railway Co. of Indianapolis, and the Hoosier Heritage Railroad Inc. of Fishers.

Nickel Plate Heritage Railroad of Arcadia proposes train operations from Noblesville to Tipton.

Hamilton County Commissioner Christine Altman says running tracks into downtown Indianapolis would be expensive and complicated. She says similar plans have been proposed before. She says a planning board study 10 years ago found the project too daunting.