My wife and I recently took a couple weeks and had an incredibly interesting trip to Utah. We explored old settlements and geological features, saw a great variety of flora & fauna, and found lots of other awesome stuff. I hardly know where to begin, but here's a few for starters:
Day 1 in Washington - an old farmstead
Day 2 in Oregon - detail on Richmond (ghost town) house, long abandoned
Day 4 in Nevada - grand old steam engine in Ely, where you can take in a very enjoyable ride
Day 4 in Nevada - again in Ely; one of the old Kennicott copper mine ore cars
Lots of rocks to come.