Alacranes or Scorpion Reef, is located 65 miles north of Progreso with Progreso been the closest point in mainland. And its a National Park protected by Mexican Law under the supervision of CONANP or National Comission of Protected Natural Areas.
It covers an area of aproximately 330,000 hectares of coral reef and islands.
Alacranes is a group of 5 small Coraline islands and atolls.   The reef complex is about 17 miles long and about 13 miles wide and only one of it’s 5 islands (isla Perez) is very lightly inhabited by the lighthouse keeper, a small mexican Navy platoon, and groups of migrant scientists and fishermen  that come and go.  The other 4 islands are named Pajaros, Blanca or Chica, Muertos or Desertora and Desterrada which is at the northern tip of the reef and none of them are inhabited or have any buildings on them.

It is believed that the name Alacranes was given to the reef by a group of spanish sailors who were shipwrecked there in 1545. This wreck, as well as probably more than a hundred others, was due to the fact that Alacranes is the only reef located right in the middle of the open ocean and in the route from the Caribbean to the ports of the Gulf of Mexico, therefore  Alacranes has for centuries been a great risk to navigators of the area, and for that reason, it is believed that in the 1800’s, a lighthouse was placed in Isla Perez by the Lloyd’s insurance company of London to prevent more wrecks.  The lighthouse we see today, is not the original Lighthouse built by the British, but the original Keeper’s house is still  there.