A giant pyramid hidden inside a mountain
I was here back in February. You can walk through some of the excavated tunnels, but most are closed off.<p>Wikipedia has a good image showing the sizes of different pyramids compared: <a href="https://upload.wikimedia.org/wikipedia/commons/3/3e/Comparison_of_pyramids.svg" rel="nofollow">https://upload.wikimedia.org/wikipedia/commons/3/3e/Comparis...</a><p>Note that Cholula has the largest base, but isn't the tallest.