After completing its grueling 2-day half-marathon through Los Angeles streets, the shuttle comes home.

Thousands of Angelenos lined the streets as the space shuttle Endeavour inched to its LA retirement home -- hours late after squeezing through a particularly narrow home stretch.

Crowds applauded as the massive white spacecraft crawled along the final straight Saturday, at the stately speed of 2 miles per hour, on the second day of its last 12-mile (19 kilometer) journey across Los Angeles.

The orbiter -- which zoomed at 17,500 miles per hour when in Earth's orbit -- had hoped to reach its final berth in the California Science Center by nightfall after its two-day slow-motion road trip.

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But as the sun set it still had several miles to go, leaving a welcoming party -- including dignitaries and thousands of shuttle fans gathered for the final homecoming ceremony -- on hold into the evening.

"I feel like it's coming back from China. It's taking so long," a 9-year-old spectator told the LA Times. Estimates suggested the shuttle would arrive from 3-5 hours late at the Science Center.

The day started with a public party for the shuttle, which left LA International (LAX) Airport on Friday morning for the relatively short -- but logistically a nightmare -- trip across town.

"What a great view, huh?" California Science Center head Jeffrey Rudolph asked the crowds in Inglewood, where the shuttle stopped for 30 minutes of speeches and celebrations, music from "Men in Black" blaring in the background.

BIG PICS: Shuttle Endeavour Dazzles Los Angeles

The final leg of the trip was not without challenges: the enormous 78-ton vehicle, mounted on a huge, computerized, multi-part transporter, had to negotiate some of the narrowest stretches of its route during the day.

Organizers had to steer the massive white craft through a series of turns -- including at least one that squeezed it to within inches of nearby buildings -- before hitting the real home straight down Martin Luther King Jr Boulevard.

Some 400 trees have had to be cut down -- initially provoking protests from locals -- and power lines turned off to make way for the vehicle.

On the final straight it was brought to a halt several times, as the spacecraft's wing-tips brushed inches away from apartment buildings, electricity poles and other obstructions.

One spectator identified as Bill, waiting at the Science Center, said he didn't care that he would have to wait several more hours to see the shuttle.

"I'm getting chills just thinking about it right now," he told the local NBC television affiliate. "It's awesome. It signified America, the United States, what we can do."

The shuttle, which flew more than 115 million miles in its two-decade career, landed in Los Angeles three weeks ago, piggy-backed on a specially-fitted 747.

PHOTOS: As Endeavour becomes a permanent resident of the California Science Center, remember the awesome power of the shuttle in this stunning photo series by Dan Winters, courtesy of Los Angeles Magazine.

Former shuttle commander Mark Kelly, who captained Endeavour's final flight, said he hoped the craft would become an inspiration for future generations of astronauts.

"Maybe someday one of these kids that see Endeavour, look up at it at the California Science Center, will be that person that walks on the planet Mars," he told CNN, adding: "That would be a great thing to see."

After NASA brought an end to the 30-year shuttle program last year, major US cities battled for the right to house the four retired vehicles.

Enterprise, the prototype that never flew into space, is now on permanent display on the runway of the Intrepid aircraft carrier in New York.

The Kennedy Space Center will keep Atlantis, and Discovery is on display at a museum outside Washington.

Two other shuttles were destroyed in flight. Challenger disintegrated shortly after liftoff in 1986, and Columbia broke apart upon re-entry to Earth in 2003. Both disasters killed everyone on board.

Crowds gathered along the streets through every leg of shuttle Endeavour's 2-day Los Angeles road trip. CORBIS