Dan Atherton has this all time, super technical ebike enduro (e)xtravaganza double black diamond ebike loop near his Dyfi Bike Park in Northern Wales.
The tour came highly recommended by Danny MacAskill, so I had to give it a go. Usually the tour requires two batteries, but we used a car shuttle for two of the five of the uphill sections. The ride is about 3000m/9000ft vertical technical trails.
I think they will eventually offer it at Dyfi as a backcountry addition to the park. I rode my GT Bicycles e-Force with Shimano Ep8 (504w)