Katie Brown has an impressive resume consisting on many extremely difficult climbs and first ascents. Alex Honnold is considered one of the best free soloists ever. Free soloing is when you climb something without a rope- just you and the rock. If you fall, you will most likely die. Not only does Alex free solo, he free solos some of the hardest climbs in the world. If you watch 60 Minutes on CBS, you may have seem a great segment on him while he was free soloing a route in Yosemite National Park. If you haven't seen the segment I highly recommend you watch it (second video below). It's pretty amazing. The formation they are climbing in the commercial though is called Ancient Art and is located just over the Colorado-Utah border near Moab. This is one of the most popular desert tower climbs due to its relatively easy and breathtaking final pitch. To really get your heart going, check out the videos below.
The Citi Bank Commercial: