Endeavour made the first U.S. mission to build the International Space Station, attaching the Unity connecting module to the Russian-built Zarya base block.
It went on to fly 11 more missions to the space station, a research laboratory owned by 15 nations that flies about 250 miles above Earth.
The United States retired the shuttles last year after the U.S. portion of the station was finished. NASA is now working on spaceships and rockets that can travel beyond the station's orbit and investing in private companies interested in developing their own spaceships to fly to the station and other destinations near Earth.
"It's been a long process to wind everything down," NASA astronaut Greg Chamitoff told Discovery News.
"For some people building parts for the shuttle, the end happened a long time ago.
"There's enough excitement now about what we're doing next. The only hard part is we don't have something sitting on the launch pad ready to go," Chamitoff said.
NASA plans two unmanned test flights of its new Space Launch System in 2014 and 2017 before the spaceship flies with a crew in 2021.