The environmentalists made their point by painting 'HOTEL ILLEGAL' in three-storey high letters across the frontage of the partially constructed building.
Work on the 20 storey, 411 room complex, which is owned by the Azata del Sol company, continues despite a court ruling dating back to February 2006, ordering construction to be halted as it is being built too close to the sea in a protected area.
While the hotel's frontage was being defaced, other Greenpeace activists in several dinghies drove round the bay carrying placards with the slogans 'Demolition' and 'Save the Mediterranean'.