Great Pyramid of Cholula (1,8 million m³). The Great Pyramid of Cholula in Mexico appears to be a natural hill topped by a Catholic church. This is the “Iglesia de Nuestra Señora de los Remedios” which was built by the Spanish in 1594 on the site of a pre-Hispanic temple. According to the Guinness Book of Records, this temple is in fact the largest pyramid ever constructed anywhere in the world, with a total volume estimated at over 4.45 million m³. This is based on a size off 450 by 450 meter and a height of 66 m.
Closer examination of the site reveals a different volume however. This complex consists of several structures starting from the third century BC. The picture below shows a huge platform. The base of the pyramid itself is 295 by 270 meters, which makes it the third largest pyramid ever built - Touropiahttps://www.touropia.com/largest-pyramids-in-the-world/