In need of U.S. vacation ideas?

Can you name a few great vacation spots for a couple.

I live in MN but it doesn’t have to be close, just in the US. (we are planning on driving).

possibly low cost

We like to hike and be outside but I would like to have lodging near by for the nights.

Don’t really want to go somewhere real tropical though (not Florida, Hawaii or islands)

Thanks a ton.