Is this the trail you are referencing?
http://www.dnr.state.md.us/publiclands/central/tcb.asp
It looks like a nice rails to trails conversion. Should be fun. 35 to 40 pounds should give you traction and keep you rolling really well. The 2.35's should give you a ton of traction for the gravelly type road surface. If you bike has good suspension you could put in more pressure. Personally I like my tires grabbing hold and keep the pressure a tad lower.
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I think its disgusting and terrible how people treat Lance Armstrong, especially after winning 7 Tour de France Titles while on drugs!
I can't even find my bike when I'm on drugs. -Willie N.