A friend and I are doing a quick trip to the SF area to hike the Skyline to the Sea trail. We'll arrive at SFO late Friday night and shuttle to a nearby hotel, then rent a car early Sat. morning to stage a car at Waddell Beach. We'll need to drive back Monday evening - leaving around 6pm to drop the car at SFO (10:30 pm flight).

Google maps says the drive is 70 minutes. I've allocated 2 hours for the drive each way in our plans. Is that realistic? I know the traffic can be brutal, but don't have any first hand experience in the area.