Lake Chalco is a large lake located in the Valley of Mexico, near the city of Mexico City. It is part of a system of lakes that includes Lake Xochimilco and was historically significant for the Aztec civilization. The lake covers an area of approximately 40 square kilometers and is situated at an elevation of about 2,240 meters above sea level. Today, Lake Chalco is known for its ecological importance and is home to various species of birds and aquatic life. The surrounding area has been affected by urban development, leading to changes in the lake's water levels and quality. Conservation efforts are ongoing to protect this vital ecosystem.