We visited part of this TWHS in the afternoon after visiting Joya de Ceren before returning back to Santa Ana. There are 3 separate zones in town of differing historical periods. We only visited El Tazumal. Somehow this area is far more touristic than Joya de Ceren, with souvenir stalls lining the street in front of the entrance to the small park. There is a small ticket office but the window was shut and the security guard let us through without paying. Locals were picnicking on the grass and resting in the shade while we checked out the small museum and then circumnavigated the restored Mayan temple that is the purpose of the place. 

This might be one of the top archaeological sites that El Salvador has to offer but frankly the temple is over restored and compared to the outstanding Mayan sites already on the list, doesn't seem to add anything new that would make it a worthwhile addition. It was a quick visit and we left disappointed and didn't bother going to the other nearby sections.