Kilian Jornet completed an unassisted speed climb from base camp to the summit in 26 hours without bottled oxygen or fixed ropes, setting a new record. The complete climb, including return to base camp, took under 40 hours, and included a vertical ascent. A standard climb using a typical route takes approximately four days from North base camp to the summit. Jornet summited again on May 28, 2017, achieving two summits in less than a week. This climb, which began at advanced base camp, took 17 hours. Jornet's speed climb was one of fastest since Hans Kammerlander completed the normal Tibet-side route in 16 hours 45 minutes in 1996, setting the official Guinness World Record. In 2005, Christian Stangl reached the top of Everest from advanced base camp in 16 hours and 42 minutes.