The general accepted strategy for trekking is to climb higher than you are going to sleep for the day to help get used to the altitude. That means we would need to climb up to the summit and then back down to the town we are sleeping in all in one day. The summit day starts in the village of Lobuche (elevation 16,200 feet) and takes about 3 hours to get to Gorak Shep, which is the last sleeping spot on the trek. Amazingly, this is the only spot on the whole trek where I had 3G internet on my phone! But I digress. After the winding, up and down slopes to Gorak Shep, it is a quick stop for lunch and then on to the summit. At this point, the daytime temperature has dropped dramatically compared to rest of the trek and we are trekking on top of a glacier. It is time to fully bundle up with the down coats, knit hats, wind-proof gloves etc. The air is super thin and it is really dry...it is quite hard to breathe. And the terrain has also changed; it is now just giant piles of loose rocks that you need to climb over. Twisting an ankle is a real concern, as is a series of rock slides from one of the thousands of loose boulders up hill from where we are walking.