Follow the Butcombe trail through the Mendips hills.

https://www.walkingenglishman.com/ldp/butcombetrail.html

This route is located in the Olympic National Forest. It consists of two connected loops and is approximately 33-35 miles in length with 12,000 feet of vertical gain. There is some scrambling, a bit of navigation involved, and somewhat unmaintained trails. There are some water sources along the route. Approximately 8.5 miles of the route are on Forest Road 2880.