Half Moon Bay, CA
Pathfinder | 140 pts
Actually did this trail as a snowshoe trip.
Beautiful walk in, although the trail is heavily used and packed down. Crampons on boots would work just as well as snowshoes, until you get to the ranger station (actually a historic registered group of buildings) where the trail loops back to Red Dirt.
The walk in from Mad Creek TH runs along the north and west side of the canyon, with the creek below. It is shady in spots, but delivers great views back towards the flattops and forward towards Copper Ridge and the further wilderness areas. There is very little elevation change, and it is pretty much a stroll - strenuous only if you increase the length by hiking east towards the wilderness area.
We did not take the loop to Red Dirt road, as the 1.5 mile shoulder walk back to the TH is not a fun idea with the snow banked up on the shoulder, removing any area to walk off the road. We did spend some time snowshoeing about 1/2 mile towards the wilderness areas - here the trail was much less traveled, and the valley wider with great views. There are plenty of elk tracks, and a full day hike back behind the ridge east towards the wilderness areas would be an easy, long and picturesque snowshoe adventure, as it travels along the creek and into some beautiful country.
So plan a longer hike than the loop, take all day to do it, and enjoy yourself. A great way to get some exercise, get acclimated and get away from the more populated ski area.