This ride can easily be done in either direction.
Starting from the south: take Limantour road into the Point Reyes National Seashore until it tops out at 790' feet. You'll see a parking area to your right with a trailhead sign. Although the Bay View Trail
will look mighty tempting, it's hiker only, so stick to the doubletrack trail that starts behind a low gate. For the first mile the trail will be rolling doubletrack but after that it starts to transition into single.
The first climb has a few steep sections but mellows out around 1000 feet. Then it's a couple ups and downs before starting the final big climb to the top. Just keep pedaling and you'll top out at a weather station/FAA facility/silo that's also the summit of Point Reyes Hill. From here you could opt to just head back down on the paved Mt Vision Road, or you could collect just a bit more singletrack by braking off to the right on a non-marked trail.
From the North: take Mt Vision Road off of Sir Frances Drake Blvd. It tops out with a parking area at 1240'. Continue straight past the FAA facility and down the big incline. Continue on the well marked trail as you pass by a number of hiking trails on your right. There's one bit of a climb at mile 1.5ish, but once you're done it's smooth sailing all the way out to Limantour Road.