Common name for a Vietnamese brothel village named Sway Pak located 11 Kilometres North of Phnom Penh in Cambodia on National Highway 5. Once notorious for housing hundreds of twenty-something, teenage and preteen prostitutes in its large brothel complexes it has now (2008) ceased 99% of its previous sex business as a result of a continuing government and NGO presents beginning in 2003. In its heyday it attracted sex tourists from all over the world and huge crowds of locals every weekend night.
Today sex tourists continue to use K11 as a noun to refer to similar spots in the third and communist world. This is a widely recognized code phrase referring to a location with an abundance of young cheaply available prostitutes.
“It's similar to K11”,
“Six for $30 just like K11”,
Where is the newest K11?”,
“Fifteen minutes walk after the border post . . . cheaper and dirtier than K11.”