Spanning across a land area of more than 140 acres, there are more than 800,000 graves at the Colon Cemetery in Havana. It is also said to be one of the most remarkable cemeteries in the world because it's the place where many tombstones of famous politicians, scientists, and artists lay in the ground. You may think you'll cover the entire area within an hour or two, but you'll surely go on for more than 3 hours.