Baxter State Park is famous for Katahdin. This is one place to stay to hike to it. It’s a very basic campground so bring your own water, though they do have canoe rentals and wood to purchase. Make a reservation. There are lean-tos and open sites, some are along the water. The best part for us was seeing so many people come down from their thru-hike and others waiting to meet their friends and family doing so. Lots of incredible energy here (and throughout Baxter) thanks to the AT.