Quarter pipe
（重定向自Quarterpipe）
A Quarter pipe is a ramp used in extreme sports which resembles a quarter of the cross section of a pipe. They are most commonly found in skateparks and a skiing/snowboarding terrain park, although the trained eye of an extreme sports fan can find them in modern day architecture. It has a progressively steepening transition, which begins at the ground, and ends at a metal rail or plastic piping called the coping. Riders/skaters may use the ramp to launch themselves into the air, landing back on the ramp transition, or to 'stall' or 'grind' on the coping.