This is the Castle San Antonio de la Eminencia.
Made by spanish colonizers in the century XXI as a military stronghold, near the venezuelan coasts, in the city of Cumaná. It has 4 towers looking to the north, south, east and west, to allow a complete view of the whole city.
An interesting fact about this castle is that its made with coral reef rocks and it is more than 500 years old, even when this region has a high seismic activity.
Oh! i almost forgot this! The people says that beneath this castle exist a huge tunnels system which go through all the city. Unfortunately the entrance to this tunnels is closed and forbidden by the local authorities.