[Pinckney]

I strongly second Muir Woods, if you have any interest in wilderness at all. I also hear that the coast is beautiful in that area, e.g.

http://upload.wikimedia.org/wikipedia/commons/2/2b/Point_Rey...

so you might visit Point Reyes National Seashore.

You probably can't ski in July, but some ski slopes will rent you mountain bikes and carry you up on the lifts, which I've heard is great fun.

The submarine USS Pampanito in SF bay might also be interesting to visit. If you're in New York, the USS Intrepid is also worth seeing.

In Florida, you can rent sub-machine guns, which might be fun.

Some of the state parks along the Florida coast are also pretty nice. You might rent a boat and sail out to the more remote ones.

Unfortunately most of my favourite places (Glacier, Canyonlands, Zion) are nowhere near any major Universities. It just depends on your willingness to travel a whole lot more than necessary.