At age 17, Barber started climbing with the Boston chapter of the Appalachian Mountain Club Although initially not athletically gifted, he became obsessed with the sport, and persevered, climbing as much as possible. By his own account, Henry climbed approximately 270 days in 1972; 325 in 1973.
In 1973, Henry did the second ascent of Foops a 5.11 climbing route in the Gunks; this was five years after John Stannard had done the pioneering first ascent. (In rock climbing, especially at popular crags like the Gunks, a second ascent is normally done soon after the first; usually in a matter of days or weeks.)
Barber was known for always climbing in his trademark white golfers' cap and white painters' pants, as well as his abrasive and arrogant demeanor. Henry was one of the few climbers of his era to actively seek and use media attention. His repertoire of moves, creativity, and problem-solving abilities, and his tremendous self-confidence and mental control, set him apart from his contemporaries.
Henry Barber was also one of the first advocates of clean climbing, climbing with only nuts for protection. Henry was an active climber before the era of spring loaded camming devices that made protecting cracks without pitons feasible. One of Barbers specialties was doing the first free ascent of established aid climbs.
Barber was a prolific soloist. He did a number of on-sight solo first ascents. In 1973, Barber soloed the Steck-Salathe route on Sentinel Rock in Yosemite National Park. The solo ascent, done on-sight in 2 1/2 hours, first brought Barber to prominence as a leading rock climber.
In 1976 Henry (along with Steve Wunsch) traveled to Dresden East Germany along with Fritz Wiessner, to be the first Americans to climb there. Wiessner had learned rock climbing around Dresden early in the century. Tradition (and soft, fragile sandstone) demanded that rock climbers use no metal for protection; relying instead only on knotted nylon slings jammed into cracks to hold a leaders' fall. Climbers were expected to climb barefoot, and to abstain from the use of gymnasts' chalk. Barber was impressed with the rigours and difficulty of climbing around Dresden; the Dresden climbers were impressed with Henry's ability, although they also thought him too reckless, especially in the area of free soloing.
Barber was well traveled, at a time when rock climbers generally didn't stray far from their home crags. His style was to show up at an area and blow the local standards out of the water. In one trip he single-handedly jumped technical standards in Australia by more than a number grade. Other accomplishments include first ascent of the often-tried Butterballs in Yosemite with an almost mystical on-sight; blazing a trail of desperate first ascents in the Gunks; on-sight free-soloing dozens of routes on many different rock types in many different countries, up to hard 5.10, at a time when the 5.11 grade was only starting to solidify. Barber climbed at Mount Arapiles in Australia; Dresden; Great Britain; Scotland; Russia; Mexico; as well as climbing all over the United States, from the crags of New England to Yosemite in California, and (seemingly) most crags in between.
In early 1978, Henry and partner Rob Taylor attempted to climb Mount Kilimanjaro in Tanzania by a new route. Taylor fell while leading steep ice, and broke his ankle very badly. The exact details of what happened following the accident vary according to which of the two parties is telling the story. What is known is that Barber helped Taylor descend; got him to a hospital; and then left to fly back to the United States to keep a speaking commitment. Taylor nearly lost his leg at the hospital, and felt abandoned by his partner. After he recovered, he wrote articles and a book, painting Barber in a very unflattering light. This incident effectively ended Barbers' career as a top climber. Barber continued to climb at a very high level after the Taylor incident, for example he plucked the first free ascent of Women in Love (5.12), Catheral Ledge, NH. Barber continues to travel world wide, climbing in his own style and learning other's styles. He eschews modern camming devices and harnesses, preferring the simpler more rigorous style of nuts and swami belt.