Three Mile Harbor Cruising Guide:
Anchorages

The anchorage area is located on the starboard side of the harbor as you enter (west to northwest side of the harbor).  The anchorage area inside Three Mile Harbor offers plenty of depth and swing room.  There is a sand and mud bottom offering a good holding ground.

In order to gain access to the anchorage you will need to follow the channel deep into the harbor.  There is a long sandbar just beyond the red channel markers.  Crossing over the sandbar at the northern parts of the harbor is practically impossible, even in a small dinghy.  You will need to pass the red channel marker "22" before turning into the anchorage. Once inside the anchorage you will find an ample amount of water with a good holding ground for anchoring.  There is a water ski area that you can not anchor in and may want to avoid due to boat wakes.  The northern and northwest corners of the anchorage area become very shallow (3-5 feet), so larger vessel will want to stay in the middle of the anchorage.

Anchoring on the Outside of the harbor...

Some boater do not like to follow the long channel into the harbor and choose to anchor outside the harbor.  During the Boy's Harbor Fireworks in July you will find many boaters anchoring outside the harbor to avoid the crowds in side the harbor.  

If you are looking to anchor outside the harbor try anchoring off of Sammy's Beach.  Sammy's Beach is on the western side of the channel, separating the inner harbor from Gardiner's Bay.  The anchorage is obviously exposed to the north and to the wakes of large passing boats, but it is protected from the prevailing southwesterly winds.

Remember free pump out services are available through the
East Hampton Harbormaster.