Thomas Dulac, born May 25, 1969, is a French climbing instructor and mountain guide. He also works as a lecturer, journalist, and author of hiking guides. It all began when, at the age of 17, he read Frison-Roche's "Premier de cordée." He then decided to become a guide. His first climb took place on the cliffs of Notre-Dame du Cros in the Aude department with his high school sports teacher. He then learned mountaineering in the Pyrenees with Dominique Sauvage of the French Alpine Club of Carcassonne: bivouacs in the snow, pitonnage, and ski touring. He went to study in Grenoble in the Alps and returned with his mid-mountain guide diploma in hand. He went on to become a climbing instructor, ski patroller, and aspiring mountain guide. Wanting to share his passion with others, he opened and equipped routes, and published his first climbing guidebook on the Pyrénées Orientales massif, then another on the Aiguilles Rouges with his friend Godefroy Perroux, which was a great success with climbers. The Sahara, in Algeria, would become his playground, where he lived for nearly nine months and opened numerous climbing routes. In 2005, he published the guidebook Climbing in the Sahara: Hoggar Massif, which precisely lists the routes he had climbed over seventy years of vertical exploration. Filled with numerous sketches and photos, it provides technical descriptions, access conditions, and more general practical information relating to southern Algeria, the desert, and local culture. After the birth of his daughter, Thomas became a caretaker at the Refuge des Cortalets, in the heart of Catalan country and the Canigou massif in the Pyrenees.