Like Chris said, the Premium loops (more Premium than any other type) are scattered throughout the Fort. There are several loops near the pool and Meadows Trading Post, campfire sing-a-long, canoe, bike and cart rentals. Here is the map linking in the Fort Info thread. If you want to be close to the pool, there are several options. 1499 (as mentioned above), 600 and 1000 are short walks over the bridge too. The main pool is a little hard to pick out on the map. It is #5.
j