This area is mostly flat or slightly rolling and dominated by agriculture. Small forest preserves closer to Indianapolis. Larger parks in the Whitewater River valley east towards Ohio.
Large FWA adjacent to an active military base. Flat hiking trails.

https://www.in.gov/dnr/fish-and-wildlife/properties/atterbury-fwa/
Short trail adjacent to a stream.

Small old growth forest preserve.

https://www.nature.org/en-us/get-involved/how-to-help/places-we-protect/shrader-weaver-woods/
Mounds SRA is adjacent to Brookville Lake, part of the Whitewater River watershed.

https://www.in.gov/dnr/state-parks/parks-lakes/brookville-lake/
Johnson County Park occupies part of historic Camp Atterbury. Flat trails.

https://www.jocoparks.com/johnson-county-park
Symbiosis forest preserve with minor hills.

Click to access Symbiosis-Brochure.pdf
Small old growth forest preserve relatively close to Indianapolis.

Another lakeside park in the Whitewater River watershed, like Mounds SRA.

https://www.in.gov/dnr/state-parks/parks-lakes/whitewater-memorial-state-park/