This goes from Bear Lake on the East Side of RMNP and to Grand Lake on the West Side of the Park, via the Flattop Mountain Trail and the North Inlet Trail. The route goes up and over the Continental Divide via Flattop Mountain.  Since Bear Lake is higher, and the west side is more gradual, it makes sense to run from east to west for an FKT.
 

The Menunkatuck Trail is a wonderful 16 mile Blue Blazed hiking trail in Guilford Connecticut. It is also the final part of the bigger 225 mile New England Trail. which stretches 200 miles from the Connecticut Shoreline to the top of Massachusetts.

Up & down:  Start at the Granite Flats Trailhead. Follow the Deer Creek/Dry Creek Trail to the high meadow. Turn left at junction in meadow onto trail toward Box Elder Peak (11,101').