Geograph - photograph every grid square

An annual piece of mountain-bike tomfoolery, organised by the fine folks of Green Events in Llanwrtyd Wells, and run around the hills just to the north of the 'smallest town in Wales'. The routes change slightly each year, but there is generally a 'long' route of 25+ miles, and a shorter route of roughly 15-18 miles. Each involves a number of fire-road climbs up the hills and technical (ie muddy and/or rocky) descents back down. There are endless opportunities for falling off bikes, and with the provision of a small amount of beer at a couple of refreshment stops in the hills, these opportunities grow as the day proceeds. Highly recommended if you like to get very muddy and make your legs hurt.
The Wobble marks the start of the annual Mid Wales Beer Festival, cycling & walking events on consecutive weekends with a certain amount of beer-drinking thrown in. The organisers are perhaps best known for the annual Bog Snorkelling championships in August.