From the team’s website,
ATI Detroit Lions 2016 Training Camp will open at the Lions headquarters and training facility in Allen Park for a tenth-straight year beginning Friday, July 29. ATI is the presenting sponsor of Detroit Lions Training Camp and is the team’s official physical therapy partner. The first day of open practice for the general public at the training facility is scheduled for Monday, August 1.
With increased attendance in recent years, the team now requires tickets for admission. They are free but must be obtained via Flash Seats.