The Six Flags Over Texas Oil Derrick is a 300-foot (91 m) tall observation tower, and an attraction at the theme park Six Flags Over Texas. Six Flags claims it to be the world's tallest land-based oil derrick (although it is actually not functional as such, and never has been). When the tower opened, it had a twelve-lane slide, attached at the first balcony level (50 ft), on which riders could slide down on using burlap bags. With two elevators holding 50 people each, the attraction has a capacity of 2000 riders per hour. The tower served as a replacement for the former Sky Hook attraction.