Boon Island, York Maine

Site Depths: 20-100ft+

Site Overview:

Boon Island is located just six miles off the coast of Maine and is home to the tallest lighthouse in New England. Though it is now an unmanned, solar powered station, it was once the home of many lighthouse keepers. It is a rocky island with coastal zones similar to what you’d expect for most of New England rocky coastlines.

What makes the island special is that it draws a number of local seals…which in turn draws the divers. Beware, as the shallows can experience a decent amount of surge as there is little in the way of nearby protection. Divers who have visited the site suggest that there is plenty to see in the 40ft range, though depths of 100ft+ can be attained.

Site Specifics:

Expect water temperatures that are colder than what you’d expect in Long Island Sound for the same time of year. Though this often results in better visibility…it is still New England, so murky water can also be expected at times.

Most of the subtidal areas in the Gulf of Maine consist of rocky boulders and cobblestones before transitioning to mud and sandy bottoms. You’ll find the rockweed covered rocks give way to kelp beds as you move away from shore. Similar to most of the New England coasts, you’ll find anemones, sea stars, urchins, lobsters, crabs, and other colorful invertebrates in and amongst the rocks. In the sand you might find moon snails, flatfish, and hake.


This site is only accessible by boat and should only be attempted by captain and crew that are familiar with the area. Assess the site before jumping into the water to observe what the surge conditions are like. Getting slammed into a rock in the intertidal zone will pose serious problems.

Corey A. Leamy 3/5/21 | CAL edited 3/8/21