The Punishment Dome was a location on the planet Varos. The dome contained various areas where rebels and dissidents were tortured, both for political reasons and for the entertainment of the citizens of Varos. Following the removal of the Mentor Sil as the only buyer of Zeiton-7 ore, the Punishment Dome was shut down.
It contained multiple locations, including the Purple Zone, an area inhabited by optical illusions, and an area filled with poisonous tendrils. (TV: Vengeance on Varos)