Claimed by both Maine and Canada, Machias Seal Island is only accessible by boat through select captains who have special permission. I was lucky to snag reservations for the 10-mile excursion on a mostly-clear day. Since the seas were relatively calm, I was given permission to climb from the boat onto the slippery landing, and spent an hour or more in one of the observation blinds on the 15-acre sanctuary. Along with the calls of terns flying overhead, you'll hear the drawn-out squawks of puffins hidden amidst the rocks, and the cheeps of chicks as a parent arrives with fish.