The side of El Capitan they have conquered is called 'Dawn Wall' and it has been described as the most difficult mountain to climb in the world. It is 914 meters tall, very steep, and rather plane. The rock face is made of granite stone and there aren't many places to hold on to.
So it took Caldwell and Jorgeson 19 days in total. They only were secured in case they would fall and they slept in tents which they attached to the mountain; a five star hotel cannot beat that. Kevin Jorgeson had some trouble on the way: because of the sharp edges he injured his hands. Therefore he needed to take a two-day break for his hands to recover.
The two men aren't the first to reach the top of El Capitan via the Dawn Wall, but they are the first to do it without using any tools and ropes.
Route to the top (source: www.bbc.co.uk)
Tommy Caldwell and Kevin Jorgeson made it to the top
Tommy Caldwell in his five star accomodation