Cape St. Mary's Ecological Reserve in Newfoundland, home to one of the largest, if not the largest colony of Northern Gannets in North America. Also thousands of Black-legged Kittiwakes, and Common Murres.
It's hard to find words that describe how magical this place is. When I visited earlier this summer, it was so fogged in at times that you could only see the birds as shadows soaring through the mist, and a bit unnerving since the edge of the cliff was at times only a few feet away.