The space shuttle Discovery circled above Washington, D.C. on Tuesday perched on a 747 jet, marking its last flight before being put on display at the Smithsonian museum.

The shuttle glided to its final landing just after 11 a.m. ET at Dulles International Airport after leaving from Florida's Kennedy Space Center early in the morning. Discovery will be towed to the Smithsonian's annex in Virginia on Thursday.

Discovery is the world's most travelled space shuttle with 39 orbital flights and almost 240 million kilometres to its name. Among its most well-known missions was flying the Hubble Space Telescope into space.

The final flight prompted mixed feelings for some who tracked the shuttle's progress – as well as the highs and lows of NASA's space program – from the beginning. Aviation analyst Mark Miller said that the mothballing of the shuttle marked the end of an era.

"It was great source of information, inspiration and story-telling," Miller told CTV's News Channel.

Crowds gathered on the National Mall in the U.S. capital to watch a stripped down version of Discovery circle at an altitude of about 460 metres, perched atop a specially modified 747 jet that NASA referred to as the "world's greatest piggyback ride."

"Look at that – that thing is mammoth," said Terri Jacobsen told The Associated Press as she watched the two aircraft fly overhead. She brought her home-schooled son to watch the flyover.

Discovery is the first of three space shuttles that will be put on display in museums. Endeavour will head to Los Angeles and Atlantis will stay in Kennedy, Fla.

NASA will now focus on building a new fleet of space ships capable of travelling deeper into outer space than Discovery or contemporaries like Columbia and Challenger. Because for all the fond sentiment the final flight of Discovery has produced, observers agree the shuttle was not without its problems.

"It's time to get something that's more efficient and is going to work better," Miller said. "[Discovery] spent a lot of time on the ground broken down."