$315k cash on hand- looking for advice.

[Spencer Fry]

I have 2 parcels of land each around 50 minutes from the east gate of Yellowstone National Park. One parcel is 2 acres and the other parcel is 17 acres. 

I was initially going to build cabins to STR since I can have 3 residences per property. Instead, I'm looking at putting in a campground/rv park on the 17 acres with some cabins as well.

Any advice? Thoughts? Tips?