The word Tulum means fence or wall, and is the name given to the site in recent times because of the wall surrounding it, although its ancient name was possibly Zama, a corruption of Zamal (morning), associated with the dawn. This is an ideal name for the site, as sunrise in Tulum is worth getting up for.
The city of Tulum was at its height during the 13th-15th century, and is thus one of the later Mayan outposts. It flourished during the 14th century and was still inhabited when the Spanish arrived in the early 16th century. Tulum was an important trading post for the Post classic Mayans. There is a beach where merchants could come ashore with their canoes. The highest building, El Castillo, was also a lighthouse to make navigation easier. When two torches aligned, it showed the way through the reef (there is a break in the reef just offshore in front of the ruins).
During the Post classic period, the Maya started to use large seagoing canoes. The canoes were 40-50 feet long and hewn from mahogany or other tropical hardwoods. These canoes revolutionized trading in the Mundo Maya. Prior to the advent of this practice, they could only move what could be carried on a person's shoulders (the ancient Mayans didn't discover the conveniences of the wheel, so land vehicles were not used). The Maya didn't use beasts of burden, simply because there were no suitable large mammals in the area. Their trading voyages ranged from trips to the Gulf of Mexico, the coast of the Yucatán peninsula, and extending all the way to what is today Honduras. There is even historical evidence that they traveled as far as Costa Rica and Panama.
The first mention of this city was made by Juan Diaz, who was on Juan de Grijalva's expedition that reached the coast of the Yucatan peninsula in 1518. In Juan de Reigosa's Las Relaciones de Yucatan, written in 1579, Zama is mentioned as a walled site with stone buildings which included a very large one that looked like a fortress. Pedro Sanchez de Aguilar, author of Informe Contra Idolorum Cultores del Obispado de Yucatan, (Madrid, 1639) mentions the coast of Zama when telling the story of ten shipwrecked Spaniards who were taken prisoner by the chieftain Kenich. Among them was Geronimo de Aguilar, who later became Hernan Cortes' interpreter during the Conquest of Mexico.
After this there are no other references to Tulum until Juan Pio Perez in a letter dated 1840 says that Juan Jose Galvez had visited Ascencion Bay, discovering that between there and Cape Catoche there were two ancient cities, Tankah (located about 15 minutes north) and Tulum, the latter surrounded by walls. In 1842, John L. Stephens and Frederick Catherwood visited tho site and later made it known to the world with the book Incidents of Travel in Yucatan, where Stephen's text is complemented by Catherwood's magnificent illustrations.