pig ear
n. A raised metal strip added to the edge of a bench or low wall as a skateboarding deterrent.
Also Seen As
San Francisco, the birthplace of street skateboarding, was also the first city to design solutions such as "pig's ears" — metal flanges added to the corner edges of pavements and low walls to deter skateboarders.
—Frank Swain, “Secret city design tricks manipulate your behaviour,” BBC, December 02, 2013
In 1999 the debate once again become a front burner issue when the city installed SkateBlocks, or "pig ears," as the police department calls them, on the raised concrete portions of the Ribbon.
—Cindy Casey, “The Embarcadero Ribbon,” Art and Architecture — San Francisco, March 26, 2013
2002 (earliest)
Adding physical obstacles such as "pig ears" (metal clips installed on surfaces to impede skating) generally won't raise the possibility of a successful suit by an injured skater, Bates says, as long as the property warns them of known hazards.
—Michael A. Gips, “Hellions on wheels,” Security Management, July 01, 2002