By Alopeus - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=113049713
Calakmul, also spelled Kalakmul, located 35 km from the Guatemalan border inside Mexican state of Campeche, was one of the major powers of the Maya lowlands, administering a large area marked by their emblem glyph, which resembles a snake head, causing modern day researchers to dub them the 'Kingdom of the Snake' or 'Snake Kingdom', and held power for a large duration of the Classic Period, from about 200-900 CE, with the city itself having an estimated population over 50,000 people and governed over locations as far away as 150 km and about 6,750 structures have been identified linked to the city with the largest being a pyramid that reaches 45 m above the surrounding area, which makes it one of the tallest Maya pyramids. Near the city is a seasonal swamp known as El Laberinto bajo, bajo being the Spanish for a seasonal swamp, that was used as a water source during the rainy season and was linked to a 'sophisticated water-control system including both natural and artificial features such as gullies and canals that encircled a 22-square-kilometre (8.5 sq mi) area around the site core', as well as providing fertile soils and access to 'abundant flint nodules' which could be used to create weapons and tools. The city itself sat on a natural limestone dome that rises 35 m above the bajo. The Maya leveled the dome to build their city, moving the settlements from the edge of the bajo, where they were in the Preclassic period, to higher ground as well as using small islands within the bajo to work flint.
By ant_mela - https://www.flickr.com/photos/ant_mela/1299347623/, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=7881874
While the city is estimated to have had a population of about 50,000 people, the Snake Kingdom oversaw about 200,000 people including 20 secondary sites such as Naachtun, Oxpemul, and Uxul, with many more living in fairly small rural communities, bringing the rural population to about 1,500,000 people, resulting in a total population of the kingdom of about 1,750,000 people in the Late Classic period in a 13,000 sq km area, a distribution greater than any other Maya city's Emblem Glyph, which can be read as 'Kaan', which indicated their control over the location.
By Sailko - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=30259807
Calakmul fought multiple wars against Tikal, being dubbed the two Maya 'superpowers', as prior to the Early Classic Period, various single Maya cities were dominant, with Tikal moving into that position in the Early Classic. Calakmul, however, had resources to rival Tikal and garnered allies of cities around Tikal so that they were able to defeat, but not eliminate, Tikal during the second half of the 6th-late 7th centuries. Tikal was able to turn this domination around in 695 and by half a century later had defeated many of Calakmul's allies. Both, however, fell under the Classic Maya collapse, the destabilization of and often violent collapse of Classic Maya civilization that occurred between the 7th-9th centuries. It's thought that the rivalry between Tikal and Calakmul was based on more than just resource competition, but also because of ideological differences rising from Tikal being influenced by Teotihuacan which placed emphasis on a single male ruler while 'Calakmul and its allies gave greater prominence to the female line and often the joint rule of king and queen'.
By PashiX - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=43663416
There are about 1000 structures in the 2 sq km core of the Calakmul site while the periphery contains smaller residential structures and cover an area of 20 sq km, of which archaeologists have mapped about 6250. Much of the construction was done in a soft limestone, resulting in severe erosion of the sculptures at the site. It was 'built in a strongly concentric fashion and can be divided into zones as one moves outward from the centre of the site' though this didn't necessarily show a class separation as there were some 'high-status residences and public buildings' among the commoner residences along the edge of El Laberinto bajo. The site also boasts the largest known Maya water reservoir, measuring 242 x 212 m, which was filled by a seasonal river during the rainy season and is still used by archaeologists today. In total, the 13 reservoirs of Calakmul hold about 200,000,000 litres, enough water to support between 50,000-100,000 people given there is no evidence that it was used for irrigation.
