I think this is a great idea and would happily travel down to Bristol to ride there. However I do agree with some of the previous comments, you need to get your finances sorted before all else, make sure you get your rent nailed down, find a suitable location and advertise the hell out of that place. Also although this is MTB site, I think that a place like this should really cater to all types of extreme sports, by including skateboarding, bmx and rollerblading you open your market up to a much larger group of people making it a more viable project. Also look at doing monthly jams for each sport, so one day a month hold a jam for BMX, one for MTB and so on, this way it offers a couple of big promo days for your park a month, allows potential sponsers to check out your park, is a good way to keep current park sponsers happy as a greater audience is seeing there products/advertising. It will especially help if you can get a company to sponser each jam and offer prizes as its a win/win situation, they get great publicity and you bring in more people. As for stuff inside the park you need to cater for all people, make sure you have jumps for all abilities, drops of varying heights and areas were beginners are seperated so they can learn in a non-threatening environment, we all remember the first time at a trail or park when you have only just started riding, its pretty daunting. Also try to think of something that isn't offered in the local area, if there aren't any foam pits nearby, you build a foam pit ect. Hopefully you can get this to work as the South-East needs something like this so best of luck to you and if you need any help with building or ideas give me a shout Dan