We visited Lower Antelope Canyon, which was absolutely amazing. Our guide, Tatanka, was wonderful. He was ever so patient with our photo-taking, answered all our questions and even volunteered to take many photos of us and showed us great spots for pictures. I loved Antelope Canyon because it is a place where you can actually touch and feel the canyon and engage with it, as you walk through the narrow slots. The colours are amazing and the light plays wonderful tricks on the rocks. Visiting Antelope Canyon was an experience I will never forget!
A few tips - you need to take a guided tour (tourists are not allowed to see the canyon on their own for safety reasons), but there is no need to make advance reservations - the tours run every half an hour and you just need to show up a little ahead of the time you want to take the tour. Also, the national park pass will not work here because it is an Indian reservation.
A tip from hearsay - the Upper canyon is supposed to be very commercial (I haven't been there, so I have no idea). The Lower canyon is not at all commercial or touristy - no souvenier shops, and it wasn't very crowded when we visited.
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