This is a single tread of the enormous Crawler-Transporter used to transport the Saturn V rocket to its launch site at the Kennedy Space Center in Florida during the Apollo program of the 1960s and 1970s. The Crawler was subsequently used for transporting the Space Shuttle. A Saturn rocket or Shuttle was mounted vertically on the Crawler.
Each tread weighs one ton. There are 57 treads per track and 456 treads total for the Crawler's eight tracks. The complete Crawler weighs six million pounds and is 131 feet long and 115 feet wide. Given its size, it traveled very slowly, reaching a top speed of only one mile per hour.
The Crawler was transferred from NASA in 1973.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.