The Bermuda triangle is located off the South-Eastern coast of United States in the Atlantic Ocean. As you can see in the map below, the area is bounded by Miami (in Florida, USA), San Juan (in Puerto Rico), and the north-Atlantic island Bermuda.
The triangle has been named after its Bermuda corner because Bermuda was once known as the 'Isle of the Devils'.
This is the most popular definition of the triangle location as per most writers and researchers. Each side of the triangle is some 1000 miles long.
The area of the Bermuda triangle has varied from one writer to the other. By the various definitions, it can be anywhere between half million to 1.5 million square miles.
Why such variations? Because some writers say that the boundaries of the Bermuda triangle also covers the straits of Florida, the Bahamas and the entire Caribbean islands. And some have added Azores and Gulf of Mexico to it.