Here are two I really liked….

The first I did just last Sunday. The cache is not a tough find by any means, but bring some climbing gear along and have some great fun. (maybe you climbers would just consider it rock scrambling? Anyhoo, I would want someone else there)

It’s at the Volga River Recreation Area near Fayette, Iowa.
http://www.geocaching.com/seek/cache_details.aspx?ID=49817

This second one is a real butt kicker, at least the way I approached it, from the north. And aided by the fact I did not take the most direct route. Even so, to get to the final location is very cool and a thrill!!!

It’s in the Reno Recreation area of the Richard J. Dorer Memorial State Hardwood Forest in SE Minnesota, not all that far from that island cache near New Albin!
http://www.geocaching.com/seek/cache_details.aspx?ID=23853