This thorough study of a 111-mile regional trail network around Columbus, Ohio found that trail users travelled roughly 11.9 million miles in 2014, mostly by bicycle. Higher population density, easy access from neighborhoods, connection to other trails, and longer trails are associated with greater use.
Ohio
The Impact of the Little Miami Scenic Trail on Single Family Residential Property Values
This study found that the Little Miami Scenic Trail in southwest Ohio is associated with higher property values for nearby properties, across the urban, suburban, and rural sections of the trail. On average, homes sell for an additional $7 for every foot closer to the trail, up to about a mile away from the trail. For example, a house a half mile away from the trail would sell, on average, for $18,612 less than a house that is identical in all other aspects but is adjacent to the trail.