Paseo Kukulkán
This archaeological dig, though small, is notable for the unusual architecture of two main plazas bounded by two streets. The majority of Maya cities had one plaza and few streets. This site may have been a royal burial ground.

Chichen Itza
This huge complex of magnificent Mayan ruins is one of the most extensive in Mexico. It dates back to 600 AD and the Mayan civilization. It features in the center the majestic pyramid of Kulkulkan, with its accompanying buildings. The ancient Maya used the observatory at Chichen Itza to track the stars and to calculate agricultural seasons.

Coba
"Coba" means "water stirred by wind," a name derived from the beatiful lakes nearby. It is one of the largest Mayan cities in existence. The Nohoch Mul is 138 feet tall.

Tulum
Tulum is the only walled city near the ocean that the Mayans ever constructed. It was built between 1200 and 1500 A.D. and is an easy day-trip away. The unique aspect of Tulum is its seaside location. As there is no place to eat at Tulum itself, many visitors pack a picnic lunch and enjoy it on the cliffs overlooking the ocean. There is a long uncrowded stretch of land to the right of the main temple. Because a trip to Tulum takes only about half a day, travelers booking tours to the site may want to select one that goes in the morning to Tulum and offers afternoon snorkeling in Xel-Ha.

Tours:

Chichen Itza
Most visitors to Cancún agree that a tour of the ruins at Chichen Itza is a must. In addition to the beautiful scenery and structures, there are fascinating echo effects in some of the enclosed areas. To streamline the tours, guides from different companies sometimes exchange parts of their groups so that one guide has the English speakers and the other has the Spanish speakers. Expect a detailed explanation of Mayan culture and history. There are also independent guides who show small parties around the vicinity. Afterward, you return to Cancún on one of the regular tour buses.

Xel-Ha
Usually, tours to Tulum also include an afternoon of snorkeling at Xel-Ha. It is a nature preserve with the lagoon as the main attraction. Don't apply any suntan lotion before coming to Xel-Ha as you are not allowed to swim with it on (it's toxic to the coral reef).