What was the Mayans most important city?

The ancient city of Tikal (in modern day Guatemala) was one of the most important cities to the Mayans. People first lived there in 500 BC, and built temples, places, houses, plazas and ball courts to play games. The city was built on a hill in the jungle, so that it was above the seasonal swamps. Up to 10 000 people may have lived in the city. Tikal suddenly collapsed in 900 AD. Nobody knows what happened to the city or its people. And it was quickly taken over by the jungle.