Aficionados gathered on Saturday at the Water Tower Recreation Center in the Chestnut Hill neighborhood of Philadelphia to play "pickleball" to mark the sport's half century mark. The sport, a mid-way mash-up of ping pong and tennis, was made up 50 years ago by a Washington state U.S. congressman and some friends to amuse their bored families after a shuttlecock couldn't be found to play badminton. Pickleball is becoming increasingly popular among aging baby-boomers who enjoy racket sports but find it  difficult to cover the ground required on a regulation size tennis court. Dan Wheeler founded the Northwest Philadelphia meetup group which now numbers over 500 members. Watch video and interviews here.