[2] As of 2020, Biggar has climbed 54 major and 17 less prominent peaks of over 6000 m in the Andes, the second highest total of anyone, after Maximo Kausch.
Biggar was the first to compile a regularised and comprehensive list of the 6000 m high peaks of the Andes, using a fixed prominence cut-off.
These ascents have been in several different ranges, including a 2005 expedition to the Cordillera Carabaya of Peru,[5] a January 2010 ascent of Medusa Northeast[6] and a November 2011 expedition to the Cordon de los Pioneros in Argentina[7] Climbing Mercedario in January 2004, Biggar became the second person, after Dario Bracali[8] to have climbed the ten highest peaks in the Andes.
[9] In February 2007 with an ascent of Incahuasi he became the second person to have climbed the worlds ten highest volcanoes, again after Dario Bracali.
In December 2015 Biggar organised an international expedition that was the first for over 20 years to climb Pico Cristobal Colon, the highest peak in Colombia.