Upper Antelope Canyon (The Crack): The more accessible of the two canyons, Upper Antelope Canyon is all on ground level and doesn’t require stairs or scrambling over rocks. Upper Antelope Canyon also offers more opportunities for those spectacular light beams due to a greater abundance of opening in the top of the canyon. If you are looking to get those iconic light beams entering the slot canyon, your chances are best if you go during midday between late March and early October.
Lower Antelope Canyon (The Corkscrew): Lower Antelope Canyon was only accessible via a series of ladders earlier in its history. Today tours can get into Lower on metal stairways. On the plus side, being the less-accessible of the canyons, Lower does keep the crowds away. For the photographers out there, lighting is typically better in the mornings due to the V-shaped slope, and shallower nature, of Lower Antelope Canyon.
Weather Warning: Slot canyons inherently come with some amount of risk. Flash floods, for instance. This is one of the reasons a tour guide is required for both of these canyons. Pay close attention to the weather during your Antelope Canyon visit. No sense in being swept away with the same sands that left such a marvel in their wake.