On the George Washington Parkway. On 16th Street NW. Interstate 66, too.

Buses, cars, people - just plain stuck as snow, sleet and ice covered roadways and knocked down trees across the region, turning the evening commute into a seemingly endless nightmare.

About 6:15 p.m., Steve Roberts, 42, began to merge his Dodge Ram pickup onto the George Washington Parkway en route to Sterling. Two hours later, he was still waiting to merge.

"I hear there's an accident up by the parkway and 495, and that's blocking everything up," said Roberts, who began his commute at the Pentagon. "I've got a long way before I get home."

Denise Borders spent nearly 13 grueling hours on the Parkway - "just sitting for hours. Literally. Sitting, not moving" - without food, without a bathroom, without sleep. There were trees down and people whose cars got stuck trying to turn around and get off the parkway, Borders said. But for most of the drivers on the road, the snow was less of a problem than the complete gridlock that enveloped them.

"You saw people get out and have to relieve themselves out in the street. It was horrible," Borders said after finally arriving at her home in Reston, close to 5:30 a.m.

On the parkway, as hour after hour passed, Borders commiserated with other drivers - parents anxiously trying to get home to their children, nursing mothers desperate to feed their infants. With their cellphone batteries slowly losing juice, the trapped drivers dialed 911 and other emergency numbers, looking for information about where to go, when the traffic would clear. No one had answers.

"I thought I was leaving early. It had just started to snow," said Borders, an educator with a global consulting firm, who left her Dupont Circle office about 4 p.m. "We still don't know what the real start of it was, but it took 13 hours to get here."

By 1:30 a.m., gridlock had turned into traffic anarchy on Colesville Road in Silver Spring. Just past Sligo, before Four Corners, frustrated bumper-to-bumper northbound drivers decided to take over the southbound lane as they attempted to climb the hill.

Except cars were still coming southbound, and snow removal trucks, too. On both sides, vehicles were stuck, including an 18-wheeler flatbed truck. Drivers - some of whom had left their offices at least seven hours earlier - were backing up, spinning their wheels, slipping and sliding.

The whole scene looked like an amusement park, like somebody had designed a real-life game of bumper cars.

In the District, at the intersection of Connecticut Avenue and Albemarle Street NW in Van Ness, buses and cars were tangled in every direction, blocking the intersection for hours. One bus blocked three lanes of Connecticut Avenue for more than two hours. A pair of Metrobus drivers - who declined to identify themselves because they said they were not authorized to speak to reporters - called it the worst travel conditions they have seen in the city during their combined 23 years behind the wheel.

"This is just bad," said one seven-year veteran as he tried to push a car that got stuck in front of his bus. "Last year was bad, but they stopped us just in time."

Metro had decided to end bus service at 9:30 p.m. The drivers had little more than an hour to go to finish up their route, but it didn't matter. They weren't moving.

Bob Kozak and Joanne Ivancic had a choice to make on their commute from the District to Frederick: Route 50 or the George Washington Parkway. They, like many others, chose poorly.

After more than two hours they had inched only two-tenths of a mile along the parkway. Their 1996 Mercury Sable - with 200,237 miles on the odometer - sat amid an unmoving chain of traffic.

Still, they were all smiles. They used the time to talk, work, and read. Ivancic popped out of the passenger seat to snap photos.

"There's the snow, and a lot of pretty colors, all these red lights, like a necklace off into the future," Ivancic said. "We're having fun with it. What else can we do?"

The two had traveled to the District as representatives of Advanced Biofuels USA, advocating for greener energy sources. They usually work out of an office at home or just a few minutes away in Frederick. This had to be some sort of cosmic punishment for the convenience they generally enjoy.

"We're always hearing about horrible commutes and the weather," Ivancic said. "I guess this is payback."

Though lighthearted about their plight, Ivancic said she was plotting a way to escape the car to use "the facilities" and was glad they had decided to gas up. They were just hoping to put a few more miles on the Sable sometime in the next few hours.

One of the worst traffic jams was on 16th Street NW, where drivers were in bumper-to-bumper gridlock from the White House to the Maryland state line. It took one Washington Post editor five hours and 20 minutes to make a six-mile trip home along that route.

A fallen tree had killed a man in his car near the intersection of Military Road and Oregon Avenue, and disabled buses and abandoned cars on 16th, Georgia Avenue and East West Highway added to the clog in the area.

One District resident left his office at Penn Quarter at 5:30 p.m. At 10, he had reached only the intersection of 16th and Montague. He was getting desperate - he lives a few miles away near the intersection of Connecticut Avenue and Military Road NW.

Through Facebook, his wife sent a message to a friend who lives near the logjam on Longfellow Street. His house had no power but the two men reunited anyway and had cold chili and a glass of wine while they waited out the storm.

The first buses began to arrive at the West Falls Church Metro station about 9:15 p.m. Many of the dozens of riders had been waiting nearly four hours.

Word had spread that Connector buses were suspending service at 9 p.m., but officials said the buses would keep running until everyone stuck at the station made it home.

Riders with smartphones and Web access passed along updates to fellow commuters from the connector Web site or loved ones monitoring the news.

About 8:30 p.m. came word that three buses were stuck about a quarter-mile away, and another half-dozen buses were stuck behind an accident on the Dulles Toll Road.

Many passengers on an inbound bus from Tysons Corner abandoned it and simply walked the remaining quarter- to half-mile on the Interstate 66 ramp to the train station in hopes of catching Metro back to their homes in Alexandria, Arlington and the District.

The final bus pulled out about 10:30 after sitting for a half-hour. And drivers still collected fares even though buses were so crowded that riders were practically sitting in each other's laps.

Staff writers Jura Koncius, Kevin Merida, Tim Craig , Debbi Wilgoren and Victoria Benning contributed to this report.