A
- AAA Chute
- A-Basin Line (aka The Nose)
- A-Basin Summit: Ramrod to Lenawee Uphill
- Abby's Way
- ABC Chutes
- Abelin's
- Abel Tasman Coastal Track
- Aberglaslyn Gorge and Cwm Bychan, Snowdonia
- Abes
- Abfahrtspiste Langeggbahn
- Abiathar Couloir
- Above the Abyss
- Abrams Falls
- Abricotine's line
- Acadia Mountain, St. Sauveur, and Valley Peak Loop
- AC Cobra
- Acer Summit via Mormon Trail
- A Chute
- Aconcagua: Base Camp Plaza Argentina to Camp I
- Aconcagua: Base Camp Plaza de Mulas to Horcones
- Aconcagua: Camp III to Base Camp Plaza de Mulas
- Aconcagua: Camp III to Summit
- Aconcagua: Camp II to Camp III
- Aconcagua: Camp I to Camp II
- Aconcagua: Punta de Vacas to Base Camp Plaza Argentina
- Action Jackson -> Andy's Loop -> Buffalo Soldier
- Adamello Race
- Adam's Gulch Loop: Medium
- Adams Key Trail
- Adelmann Mine
- Adirondack Great Range
- Adirondack Great Range Loop
- Adobe Jack -> Javelina Loop
- A Double Century loop over the highest highway in Canada: Highwood Pass
- Adula Bivi Hut to Splügen
- Adulam and Kanim Loop
- Aerothlon Pemberton - Bike Route
- Aerothlon Pemberton - Paragliding Route
- Aerothlon Pemberton - Speed Hiking Route
- Aflow Daddy Shuttle
- After Atlantis (Connector Trail)
- Afternoon Delight
- Agate House and Long Logs
- Agua Mineral Araucania Backcountry
- Aguille du Midi - Hike to Mer de Glace
- Ahornspitze Peter Habeler Weg
- Ahornspitze via the Popbergschneide
- Aiea Loop Trail
- Aiea Loop Trail
- Aiguebelette - Circuit 9
- Aiguille Carree, Northeast Couloir
- Aiguille d'Argentière via the Glacier du Milieu
- Aiguille de la Grande Sassière
- Aiguille de la Grande Sassière Summit
- Aiguille de la Grande Sassière to Le Chevril
- Aiguille de Moine, 3412m. S Face
- Aiguille D'Entreves
- Aiguille d'Entrèves traverse
- Aiguille de Péclet Face Ouest
- Aiguille de Toule, N Face
- Aiguille du Argentière, Couloir Barbey
- Aiguille du Argentiere, Y Couloir
- Aiguille du Chardonnet, South Couloir
- Aiguille du Chardonnet, West Couloir
- Aiguille du Midi, 3842m. Cosmiques Arête
- Aiguille du Midi - Randonnée à la Mer de Glace
- Aiguille du Rôchefort South Face
- Aiguille du Tacul Northwest Shoulder
- Aiguille du Tour, 3540m
- Aiguille Grive - Col d'Entreporte
- Aiguille Grive North Couloir
- Aiguille Grive North-West Shoulder
- Aiguille Pourrie
- Aiguille Qui-Remue North Face
- Aiguille Rouges North Face
- Aiguilles Marbrées Traverse
- Aiguille to Montgenèvre
- Aiguille Trees
- Aiguillette Couloir
- Aiguillette des Houches
