I read the route guide in the latest magazine today - it surprised me with the choice of the medium and hard routes. I've done the "hard" route - the Gap route - and then gone out to do a little bit more; the "medium" route - the Black Mountains "killer loop" - was when I decided that full suspension was the future as I was utterly broken by the end!
The Gap route has two hills that are mostly a fairly easy spin up; the Black Mountains route has two b*st*rd climbs and a 1/2 hour push. The descent down Rhiw Trumau in the Black Mountains is also much harder than anything on the Gap route.
I know which I'd do if I wanted a bit of an easier ride...

