LOS ANGELES - At its prime, the space shuttle Endeavour circled the globe at 17,500 mph (28,160 million kph), faster than a speeding bullet. In retirement, it's crawling along the streets of Los Angeles at a sluggish 2 mph (3 kph), a pace that rush-hour commuters can sympathize with.    

Endeavour's two-day, 12-mile (19 kilometer) road trip to the California Science Center where it will be put on display kicked off around midnight Friday. Rolled on a 160-wheeled carrier, it left from a hangar at the Los Angeles International Airport, passing diamond-shaped ''Shuttle Xing'' signs, and reached city streets about two hours later.

Hundreds of spectators waiting in the predawn darkness snapped photos and gaped as the 170,000-pound (77,111-kilogram) Endeavour inched by with its tail towering over streetlights and its wings spanning the roadway. Some had pajama-clad children in tow.

The shuttle made stop-and-go progress, with some halts to check its balance and to prune trees in its path as it rolled past strip malls and storefronts.   In a massive feat of parallel parking, the shuttle was backed into a shopping center parking lot around 5:30 a.m. - later than expected.

Janet Dion, a family therapist, was in awe to see the shuttle, its sides weathered by millions of miles in space and two dozen re-entries.

''It's exciting to see the tiles up close, especially the texture of the tiles,'' she said. ''It's amazing. You can almost feel the fabric of it, like a skin. Like our skin.''

Endeavour will remain at the parking lot for a nine-hour layover as crews worked to widen the carrier so that it could straddle the median during the next part of the trip. It was expected to move again in early afternoon then stop for several more hours to transfer to a special dolly for the cross over the busy Interstate 405 at night.

Ushering a shuttle through an urban core is a logistical challenge that took almost a year to plan. Guarded by a security detail reminiscent of a presidential visit, police enforced rolling street and sidewalk closures as early as Thursday night in some locations and discouraged spectators from swarming side streets.

The behemoth transport has caused headaches for shopkeepers along the route who counted on cheering crowds jamming the curbs to boost business.

In the days leading up to Endeavour's move, the owners of Randy's Donuts sold shuttle-shaped pastries emblazoned with the NASA logo and even hung a shuttle replica inside the giant doughnut hole sign visible from the busy Interstate 405.

Co-owner Larry Weintraub planned to watch the shuttle creep by the roadside sign, which has been featured in several movies. But the store, which serves up sweets 24-7, will be closed Friday night.

''I'm still excited, but I'm disappointed that people aren't going to be able to stand in the streets and shout 'Yay,''' he said.   Saturday is typically the busiest day for James Fugate, who co-owns Eso Won Books in South Los Angeles. But with Endeavour expected to shuffle through, Fugate braced for a ho-hum day in sales.

''We don't close because we're slow. That's when you pull out a book to read,'' he said.

The baby of the shuttle fleet, Endeavour replaced Challenger, which exploded during liftoff in 1986, killing seven astronauts. It thundered off the launch pad 25 times, orbited Earth nearly 4,700 times and racked up 123 million miles (200 million kilometers).

Last month, it wowed throngs with a dizzying aerial loop, soaring over the state Capitol, Golden Gate Bridge, Hollywood Sign and other California landmarks while strapped to the back of a modified 747 before finally landing at LAX.

The last leg of Endeavour's retirement journey skips the tourist attractions and instead, winds through blue-collar communities in southern Los Angeles County. While viewing will be severely curtailed due to sidewalk shutdowns, crowds are still expected.

Moving the Endeavour required a specialized carrier typically used to haul oil rigs, bridges and heavy equipment. The wheels can spin in any direction, allowing the shuttle to zigzag past obstacles. An operator walks alongside, controlling the movements via joystick. Several spotters along the wings are on the lookout for hazards.

To make room for the five-story-tall shuttle and its 78-foot (24-meter) wingspan, some 400 trees were chopped down, cable and telephone lines were raised, and steel plates were laid down to protect the streets and underground utilities. Endeavour will mostly travel on wide boulevards with some boasting as many lanes as a freeway.

While there have been advance preparations, there is remaining work to be done during the move, including de-energizing power lines. Southern California Edison warned of outages in the suburb of Inglewood.

One of the trickiest parts involves trundling through a narrow residential street with apartment buildings on both sides. With Endeavour's wings expected to intrude into driveways, residents have been told to stay indoors until the shuttle passes.