Lower Antelope Canyon
Known for its stuning beams of light. (April-September sunny days around 11:30).
Overcrowded as hell.
In photo tour, the guide might help to visualize them by throwing sand into them.
Yet through the whole photo tour ordinary groups are passing the location, so it's rather a frustrating experience I recommend only to those who really need to do their own of the same thing. Not sure if there are times where there is more than seconds between the tourist groups passing by.
Must be booked in advance.