The Yucatan Peninsula is very rich in the history of the Mayan civilization. From AD 250-1500, the Mayans prospered and created spectacular palaces and temples in their city centers. The Maya honored scholars and astronomers and the structures they built are nothing short of architectural engineering marvels. The buildings usually incorporated the location of the sun, moon, stars, and planets. There are many tours available to visit the ruins, including transportation, admission, tour guides, and often lunch. Some tours are bundled with a visit to nearby attractions. If you visit on your own, there are usually guides available for hire by the entrance and I highly recommend it. The detailed history can't be appreciated through a guidebook alone.
From the resort areas of the Mayan Riviera, the ancient ruins at Tulum are the easiest to visit, being only about 40 miles south of Playa del Carmen. To visit on your own, it's a quick drive down highway 307, and entrance and parking fees are very reasonable. If not renting a car, taxis and public buses (collectivos) can also get you there easily. Be aware that bringing a video camera incurs an extra fee. Tulum is big enough to feel like you got a dose of education, but small enough that you don't need a whole day for the visit. It's an excellent introduction to the Mayan culture, and very do-able with children.
Tulum is perched on a cliff 40 feet above the turquoise Caribbean with spectacular photo opportunities at every turn. The site is surrounded by an enormous wall totaling about 2400 feet in length, an average of 16 feet in height, and about 8 feet thick. Inside the wall, the ruins cover a relatively small area with about a dozen structures. The most well known is "El Castillo" (the castle). Its location on the cliff is thought to have been a Mayan lighthouse, marking the exact spot of a break in the coral reef for canoes to come to shore safely. Two windows in the castillo's sea-facing wall functioned as range lights. At night when viewed from the water, the two lights would only become aligned vertically if a ship was on the correct bearing.
The Mayans revered nature and the temples of the sun and wind were built to worship the respective gods of the elements. Mayan spiritual leaders made some very important calculations to determine where their structures would go. During the Spring and Winter solstice, the sun aligns perfectly with the doorway and center of the Sun Temple. The Temple of the Wind registered the actions and force of the wind and warned the Mayan community when hurricane were forming.
Plan on visiting early in the day-at opening time if possible. Not only will it be less crowded, but it will be much cooler, since there's no shade. Don't forget water and sunscreen! Even though climbing on or in the structures is not allowed, wear good sneakers to walk around the whole site. Allow two to three hours for visiting the ruins, then make your way down to the breathtaking private beach which is included in your admission fee.