Nudity
Until the 1990s in the United States, public swimming pools such as at the YMCA allowed parents to bring young children into the changing rooms. The children could see adults and other childen of either sex nude. There was sometimes no specific age limit for the children, but in some places up to age 6. Soon after, rules were changed allowing only same-sex use of changing rooms. At some places today, family changing rooms have been added.