Markleville is a town in Adams Township, Madison County, Indiana, United States. It is part of the Indianapolis–Carmel–Anderson metropolitan statistical area. The population was 484 at the 2020 census.

The Indianapolis metropolitan area is an 11-county metropolitan area in the U.S. state of Indiana. Its principal cities are Indianapolis, Carmel, Greenwood, and Anderson. Other primary cities with populations of more than 50,000 include Fishers, Noblesville, and Westfield. Located in Central Indiana, it is the largest metropolitan area entirely within Indiana and the seventh largest in the American Midwest.