How many islands?

How many eggs are in a dozen? Sounds like a goofy question, but ask an Upstate New York local how many land masses comprise the 1,000 Islands and you’ll hear a very different number — 1,864, to be precise.

Islands within this St. Lawrence River archipelago range in size from over 40 square miles with multiple structures to tiny uninhabited rock outcroppings. So, what’s the criteria for actual “island” designation?

One square foot of emergent land must remain above the water year-round and support at least one living tree. That means a lot of modest dots of land enjoy membership in the “1000 Islands” family, but there’s plenty of notable islands awash with legends and lore. Among them:

Heart Island — Home to the opulent Boldt Castle (founded by former Waldorf Astoria Hotel Group President, George C. Boldt)

Wolfe Island — With more than 30,000 acres, the largest island sits entirely in Ontario, at the meeting of Lake Ontario and the St. Lawrence River.

Just Room Enough Island (aka Hub Island) — At 3,300 square feet, this is known as the smallest inhabited island, with a house, a tree, shrubs and a small beach.

Grindstone Island — The fourth largest island is home to Potters Beach, one of the only naturally occurring sandy beaches in the 1,000 Islands

Dark Island — In 1905, the stone structure originally known as The Towers, was built by Singer Manufacturing Company President Frederick Gilbert Bourne, who later renamed it Singer Castle.

Carleton Island — The now-ruined Fort Haldimand was built here in 1779 by the British during the American Revolutionary War. During the War of 1812, the island was captured by three American soldiers and remains part of the United States.

Deer Island — Sitting a couple miles north of Alexandria Bay, this one’s owned by the secret society of Skull and Bones.

Longe Vue Island — Located across from Alexandria Bay, near Boldt Castle, this is the only manmade site in the 1,000 Islands.

Ironsides Island — The uninhabited rocky island near Alexandria Bay is home to one of northern New York’s largest great heron rookeries. (Listed as a National Natural Landmark, 1967).

For narrated tours of the 1000 Islands, visit