Idaho -- Where to go?

My daughter and son-in-law just moved to Boise and we are planning to go out to visit them in early September and then take 7 - 10 days exploring the area. Looking for ideas on places to go for hiking, landscape photography, and wildlife -- and maybe sneak in a little trout fishing. What are some must sees?

Had thought about going to Yellowstone but looks like all of the lodging is booked. Will have to plan that trip further in advance. We will rent a car -- right now the slate/schedule are wide open. Any recommendations?

Thanks for any help.

Not sure how far you want to drive, but Glacier NP is amazing and covers landscapes and wildlife. Shorter trip you could get into Eastern Oregon, the Painted Hills are beautiful along with so many other places around that area.