Unless you go to Llandegla, you will be doing a lot of climbing to reap the rewards, but the rewards are worth it!
Start at the Sun Trevor and make your way up the Panorama (as high as you can go). Head over to World’s End along Offas Dyke and enter Llandegla via the sleepers climb.
Go through the style/gate and *immediately turn left and bike up until the next style. Hop over this and ride upto the masts – to the second tower. You will see a small slither of singletrack to the rear of the mast building.
Follow this down to the stream, and cross back up the other side. Then ride the next bit until the stream and ride back upto the road. Then just retrace your route back to the Sun Trevor.
If you feel you have plenty in reserve then at the point where I’ve inserted a * above don’t go left, go straight and do a lap of Llandegla. You will be 2/3 of the way up the 3 mile climb at that point so you can do the blue, red or black.
All of that would be a solid 25-35 miles or so I should imagine.