5 mile trail run around Georgia's Stone Mountain park.  The CCW direction has a Strava segment, but you can go either way (whichever way is faster).

Flitch Way:  Essex, just outside Bishop's Stortford to Braintree.

A 40 mile moderately trafficked point to point National Recreation Trail. It runs along large creek (the black creek) and it’s terrain is considered easy to moderate with a little under 2,000 feet of elevation gain.