Tunnel of Doom
From the Super Mario Wiki, the Mario encyclopedia
In The Super Mario Bros. Super Show! episode "On Her Majesty's Sewer Service", Mario and Luigi were dropped into the Tunnel of Doom after Vampa White spun the "Tunnel of Doom" space while playing the Wheel of Misfortune.
Escape from the tunnel is fairly difficult, as the only way in is through being dropped down from above. As such, one needs to find a way to reach the high opening in order to escape from the tunnel.