The cli-machx was built in 2005 by ecotrails and is sited in the Dyfi forest; home of the Howies Dyfi Enduro.
It's a 15km round trip, with 9km of built single track with compressions and whoops, rock slab drop offs and some beautiful flowing turns.
The last descent is the longest in Wales and features rocky jumps; watch out for the 'eye of the needle'; a huge jump with a narrow landing between two trees on the other side.
The finale is a sequence of eight huge berms following quickly after each other. Hit them high enough and fast enough and they ride really well, but don't look down!
There's also plenty of informal free-riding in the forest, but it isn't waymarked, so take a map or get a local guide.
The Holey Trail
bike shop in Machynlleth has maps of specific recommended routes in the Dyfi, and cross-country routes in the area.
This trail is graded as red, although the second half of the last section (Tony the Tiger) is graded as black.
The cli-machx is 4 miles north of Machynlleth, a pleasant ride along National Cycle Route 8. There are no facilities at the trail head but there is a pub [Tafarn Dwynant
] that serves food in neighbouring Ceinws a couple of hundred metres away.