The Kasha-Katuwe Tent Rocks National Monument is one of the most amazing places I've been in the United States. It's located not too far from Santa Fe (definitely day trip worthy), and the entrance fee to get into the park was only $5, which I thought was a steal. It reminds me of the Antelope Canyon, but less crowded. Once you get parked, you are able to walk at your leisure through huge columns of rock that were created by volcanic explosions, but have been worn down by nature and the elements over the years. There is a lot of walking involved here, but it's something you won't quickly forget!