Coba (Spanish: Cobá) is an ancient Maya city on the Yucatán Peninsula, located in the Mexican state of Quintana Roo. The site is the nexus of the largest network of stone causeways of the ancient Maya world, and it contains many engraved and sculpted stelae that document ceremonial life and important events of the Late Classic Period (AD 600–900) of Mesoamerican civilization. The adjacent modern village bearing the same name, reported a population of 1,278 inhabitants in the 2010 Mexican federal census.

The ruins of Coba lie 47 km (approx. 29 mi) northwest of Tulum, in the State of Quintana Roo, Mexico. The geographical coordinates of Coba Group (main entrance for tourist area of the archaeological site) are North 19° 29.6’ and West 87° 43.7’. The archaeological zone is reached by a two-kilometer branch from the asphalt road connecting Tulum with Nuevo Xcán (a community of Lázaro Cárdenas, another municipality of Quintana Roo) on the Valladolid to Cancún highway.

Coba is located around two lagoons, Lake Coba and Lake Macanxoc. A series of elevated stone and plaster roads radiate from the central site to various smaller sites near and far. These are known by the Maya term sacbe (plural sacbeob) or white road. Some of these causeways go east, and the longest runs over 100 kilometres (62 mi) westward to the site of Yaxuna. The site contains a group of large temple pyramids known as the Nohoch Mul, the tallest of which, Ixmoja, is some 42 metres (138 ft) in height. Ixmoja is among the tallest pyramids on the Yucatán peninsula, exceeded by Calakmul at 45 metres (148 ft).

Coba was estimated to have had some 50,000 inhabitants (and possibly significantly more) at its peak of civilization, and the built up area extends over some 80 km². The site was occupied by a sizable agricultural population by the first century. The bulk of Coba's major construction seems to have been made in the middle and late Classic period, about 500 to 900 AD, with most of the dated hieroglyphic inscriptions from the 7th century (see Mesoamerican Long Count calendar). However, Coba remained an important site in the Post-Classic era and new temples were built and old ones kept in repair until at least the 14th century, possibly as late as the arrival of the Spanish.

The Mayan site of Coba was set up with multiple residential areas that consisted of around 15 houses in clusters. All clusters were connected by sacbeobs, or elevated walkways.

Six major linear features were found at the Coba site. The first feature that was often found at Coba was the platforms that were connecting the clusters to the sacbeobs. These were found at almost every single cluster of houses. Single or doubled faced features that were found around the majority of the household clusters. These were often linked to the platforms that led to the sacbeobs. A lot of features found tended to connect to something or lead to something but the other end was left open-ended. Coba has many features that are platforms or on platforms. The last major linear feature that was constantly found was sacbeob-like paths that were someway associated with natural resources of the area.

Cobá lies in the tropics, subject to alternating wet and dry seasons which, on average, differ somewhat from those in the rest of the northern peninsula, where the rainy season generally runs from June through October and the dry season from November through May. At Cobá, rain can occur in almost any time of the year, but there is a short dry period in February and March, and a concentration of rain from September through November.