Things to do if you make it to Guam: Pagat cave.
A nice hike that’s about 75% shaded. The trail splits: walk down to the coast where you can usually jump off, but it was kind of rough when we went so we didn’t, and on the way back stop off and go down into the cave and take a dip in the water. The only place I’ve been to on Guam so far where the water was actually cold. We managed to get by with a dinky flashlight and two cell phone lights, but definitely bring more lights than we did because its pitch black down there.