One of the best perks of traveling is that you get to see natural wonders up close. Visit a massive crater, and you’ll find yourself reflecting upon the vastness of the world and your tiny role in it.

Bowl-shaped, hollowed-out craters are formed by volcanoes, meteorites and other explosions. They’re found all over the world and they come in all shapes and sizes. One of the largest – Tanzania’s Ngorongoro Crater --is more than 100 miles wide and 2000 feet deep.

Here are some of the world’s most jaw-dropping craters. You have to see them to believe them.