The clock started at 8 p.m. Friday. Crews needed almost every minute of their 57 hour window to tear down Doyle Drive.
"The weekend was amazing," said project spokesperson Molly Graham.
The first cars breezed through the new tunnel and over the fresh pavement at 4:45 a.m. - 15 minutes ahead of schedule. But the pace slowed to a crawl as the morning went on.
"The commute has always backed up, there is no question, the peak period always bogs down. You are coming into city streets with a traffic light - so that is just the way the commute goes. We do expect with the new configuration that it will take a little while and it will create a bit of a backup for the first couple of weeks" said Graham.
The CHP will have extra patrols in the area through today as drivers get used to not only the tunnel, but a new curve and a new 35 mph speed limit. At least one driver already got a speeding ticket this morning.
Pedestrians along Marina Green are taking it slow enjoying the view. One man just didn't feel like waiting for his usual shuttle.
"Obviously with the construction - you are pretty much waiting longer. It's a nice morning walk, you can seen the bridge and everything," said San Francisco resident Robert Lufus.
The appearance of the $1.1 billion project is secondary. The true purpose is safety.
"The biggest milestone is that we have seismic safety and we also have traffic safety," said Graham.
Part of the new safety is a moveable median the lines most of the route. The total project will be done in 2015 and will include three more tunnels. It will also have an interchange that connects directly to the Presidio.