today I covered this loop except I started from South parking lot of purisma which is by skyline Blvd hwy 35. There are space for about 12 cars. however this entrance is much less popular and only have couple of cars Wednesday morning at 10:30. from here it's a gentle 1.8 miles downhill fire road to intersection of Craig Britton trail. once down to purisma creek, it's a flat trail all the way to Higgins road trail head which is pretty popular with about 12 cars parked. the flat creek trail has more people, I ran into 10 hikers and one biker. at early November, the creek is still flowing, a little miracle for peninsula. from Higgins to Harkins ridge trail is mostly exposed and hence dusty just like other south Bay trails. from this point to intersection of Craig Britton trail is all uphill with couple of steep sections. this part of Harkins ridge trail is not pleasant. then comes the beautiful part once I turn into Craig Britton trail which is gentle downhill narrower hiker only trail. it's in the redwood Grove and shady all the way. this trail is as enjoyable as the flat creek trail. there are fewer people on either Harkins ridge or Craig Britton trail. then I turned back to South parking lot. this route is 10.7 miles long with 2297 feet up and 2297 downhill according to Google maps. Google estimate 4.5 hours for the route. it took me 5.2 hours. it's a good hike.