Dateline | September 06, 2013
>> narrator: in mid-may, hundreds of climbers left everest base camp for the summit. they were all trying to squeeze through that narrow two-day weather window and reach the top of the world . when jon kedrowski and maria figured out how crowded it would be, they decided to wait.
>> narrator: sriya shah left with the crowd and started climbing the mountain, filming as she went. most climbers take four days to get from base camp to the summit. they pass through camp one on the first day, then spend a night each at camps two and three, then reach the higher camp, camp 4 , in the death zone . climbers don't stay there overnight, they simply rest there a few hours before the final push to the summit. jon kedrowski and sandra laduke knew they would encounter one of the mess treacherous parts of the climb right away.
>> from base camp to camp two, you have to go through the kudro ice fall. there are constant avalanches into the ice fall, huge towering racks of ice that can topple at any time. and you hear them cracking as you're walking through.
>> narrator: the weather was warmer than usual, threatening to melt those towers of ice called saraks and send them crashing down on the climbers. to get cross, climbers have to walk across flimsy ice ladders carrying all their gear, and wearing those spikes or crampons on their boots.
>> sometimes you can't see the bottom. the crevasses are really deep. the trick is not to look down.
>> to the viewers a at home, i want to show everybody how deep that thing is.
>> it's pretty deep.
>> pretty deep.
>> as sandra and jon were climbing, they saw the climbers who left ahead of them and felt good about their decision to be a day behind. the first close call of their journey. an avalanche wiped out camp three one day before they arrived. when kedrowski hiked up through the next day, he saw how close they had come to being buried.
>> we're at camp three, and there was an avalanche that destroyed our entire camp.
>> narrator: the avalanche could have killed more than a dozen people if they had been in those tents at the time.
>> you just to hang in there and hang tough and get it done.
>> narrator: so kedrowski and laduke continued their climb. sriya shah hadn't waited. she was already 4,000 feet above them at camp four, getting a few hours rest before her summit push. sriya shah and about 100 other climbers left their tent and set out for the summit. they had now entered the so-called death zone , where most climbers can't breathe on their own and require supplemental oxygen. it's where temperatures are the lowest. from now on every step that sriya shah took would be more dangerous. sriya was completely dependent on that oxygen. the two sherpas climbing with her carried extra tangings.
>> looking back at every rs, you were able to see the head lamps of people marching up. it was almost like the stars behind mt. everest. i had no idea that what i was watching unfold five miles across the valley was one of the worst tragedies in everest history.