mid day. Light beams start to peek into the canyon March 20 and disappear by October 20. Lower Antelope Canyon Lower Antelope Canyon, called , or 'spiral rock arches' by the Navajo, is located several miles from Upper Antelope Canyon. Prior to the installation of metal stairways, visiting the canyon required climbing pre-installed ladders in certain areas. Even following the installation of stairways, it is a more difficult hike than Upper Antelope. It is longer, narrower in places, and even footing is not available in all areas. Five flights of stairs of varying widths are currently available to aid in descent and ascent. At the end, the climb out requires flights of stairs. Additionally, sand continually falls from the crack above and can make the stairs slippery. Despite these limitations, Lower Antelope Canyon draws a considerable number of photographers, though casual sightseers are much less common than in the Upper canyon. Photography-only tours are available around midday when light is at its peak. Photographers cannot bring a tripod. The lower canyon is in the shape of a "V" and shallower than the Upper Antelope. Lighting is better in the early hours and late morning. Flash flooding Antelope Canyon is visited exclusively through guided tours, in part because rains during monsoon season can quickly flood it. Rain does not have to fall on or near the Antelope Canyon slots for flash floods to whip through; rain falling dozens of miles away can funnel into them with little notice. On August 12, 1997, eleven tourists, including seven from France, one from the United Kingdom, one from Sweden and two from the United States, were killed in Lower Antelope Canyon by a flash flood. Very little rain fell at the site that day, but an earlier thunderstorm dumped a large amount of water into the canyon basin upstream. The lone survivor was tour guide Francisco "Pancho" Quintana, who had prior swift-water training. At the time, the ladder system consisted of amateur-built wood ladders that were swept away by the flood. Today, ladder systems have been bolted in place, and deployable cargo nets are installed at the top of the canyon. A NOAA Weather Radio from the National Weather Service and an alarm horn are on hand at the fee booth. Despite improved warning and safety systems, the risks of injury from flash floods still exists. On July 30, 2010, several tourists were stranded