Answer:
Figures vary, but according to the Australian Institute of Marine Science, the Great Barrier Reef is approximately 2,300km long. It is located in the Coral Sea and lies parallel to the coast of Queensland. It is actually a series of reefs and atolls, with its northern end just south of Papua New Guinea, and its southern end near Lady Elliott Island, northeast of the city of Bundaberg. This is the equivalent of about 1,430 miles.
Australia has almost one-fifth of the world's reef area and most is located in the Great Barrier Reef, off the eastern coast. The Great Barrier Reef World Heritage Area, which comprises more than just the coral reefs, atolls and islands of the Great Barrier Reef, covers around 348,000 sq km (134,363 sq miles) while the Great Barrier Reef Marine Park itself covers around 344,400 sq km.