sentences:  It has been damaged by two looters' pits, one of which was sunk into the summit resulting in serious structural damage and exposing a vaulted chamber with an intact doorjamb on its north side.The corbel vault and parts of the walls still retain their original stucco covering, the remains of which have revealed that the chamber was originally painted red, possibly together with other colours.Structure L7-18 has been dated to the Early Classic based on its architectural style.