Redwood Creek Trail

This fire road is signposted Deer Park Fire Road, and also on the OSM base map for Komoot and most GPS apps. It connects to Redwood Creek Trail going south west along Muir Woods Rd to Muir Beach, and for a short 50 yards connecting to old Mill Rd on Cardiac hill.
Continue on Old Mine Trail komoot.de/highlight/198544 towards Pantoll komoot.de/highlight/198543 to stay on a longer tour to Mt Tam or north along the ridges komoot.de/tour/13627075

This trail is also known as Deer Park Fire Road, depending on which map you use. It starts with a serious climb, but not discouragingly steep. Its steepest part (which is the first half) averages 12% grade. It then eases up a little bit. Then the last third of it has a slope of 11% once again. While the route is mostly under tree cover, views open up to the neighboring hillsides once in a while.

The historic Dipsea Trail parallels Redwood Creek Trail (or Deer Park Fire Road) for the whole length of this climb. This is one of the worthwhile things you'll be seeing on this ride (not that you'll be experiencing it first hand, because bikes aren't allowed on Dipsea Trail). The trail crosses Deer Park Fire Road back and forth at multiple spots but never deviates from it significantly for the duration of this climb. This trail dates back to the Mexican era of California and is believed to have been blazed by the Miwok before Europeans arrived here. It's also the course for the famous annual Dipsea Race, which is stated to have the distinction of being the oldest trail running event and the second oldest foot race of any kind in the US.