It are thousands of ancient structures at Tikal and only a fraction of these have been excavated , after decades of archaeological work . The most prominent surviving buildings include six very large pyramids , labelled Temples I - VI , each of which support a temple structure on their summits . Some of these pyramids are over 60 metres ( 200 feet ) high . They were numbered sequentially during the early survey of the site . It is estimated that each of these major temples could have been built in as little as two years .