After waiting 37 years for a Super Bowl championship, the 12th Man had to wait a few hours more to travel by car, bus, train or ferry before reaching the victory party downtown.

Crowds estimated by police at 700,000 people strained the transportation system to its limits, though Seahawks fans kept their cool.

Ferries carried about 20,000 passengers to Seattle in the morning and floated them back out in the afternoon, three times the usual number.

The afternoon commute began an hour early, after the parade downtown and party at CenturyLink Field.

Drivers still had a fighting chance to reach the north suburbs — until wrecks blocked both Aurora Avenue North in Shoreline and Interstate 5 in Lynnwood just before 4 p.m. By the time crews cleared the Interstate 5 wreck, backups reached nine miles. State highway staff called it “GridHawk.”

There’s been nothing like it.

The closest comparison might be “Viadoom” in October 2011, when the Alaskan Way Viaduct closed for a week of demolition in Sodo, and traffic rippled to Bothell. A sequel is due this spring, presuming that now-idle tunnel-boring machine Bertha descends beneath the viaduct, prompting the state to suspend traffic as a precaution.

King County Metro Transit added 60 buses for Wednesday’s morning crush, but says they were slowed by traffic. Sound Transit added trains in the morning and still left folks behind.

So like Denver QB Peyton Manning yelling “Omaha,” officials called an audible for the afternoon.

Sound Transit added a 10th southbound train leaving Seattle at 6:30 p.m. for Lakewood.

Link light rail, which ran just six minutes apart all day, expanded three of its two-car trains to four cars — each holding 600 people or double the normal capacity.

Community Transit added buses to head north, while Sound Transit added 30 Pierce Transit buses to handle crowds going south.

Leaving town could still be a struggle.

Season-ticket holders Paul Navarrette and Deana and Greg Michael, coming from Kitsap County, parked near SeaTac/Airport Station but couldn’t catch a light-rail train after two hours, so they took a cab.

After the parade, they again tried, and failed to get on a train. They walked north to Pioneer Square Station and struck out. Finally they boarded at Westlake.

Luck smiled on Gary Filcher of Selah, Yakima County. He and a friend drove and arrived around 1 p.m., parked a mile south of the stadium and had time to kill.

“We were really surprised. We must have just been behind the rush,” he said.

He lingered afterward in the stadium gift shop to avoid traffic, met cornerback Richard Sherman’s mother there and took a picture with her.

“Man, this week has been really special. It just keeps on getting better and better,” he said.

Staff reporters Lynn Thompson and Alexa Vaughn contributed. Mike Lindblom: 206-515-5631 or mlindblom@seattletimes.com. On Twitter @mikelindblom