This is a good hike to knock out if you're short on time, live in the area and don't want to waste time driving. You still get great scenery, a bit of wildlife, moody weather, and more and yet you can launch just outside of Portola Valley. But on the flip-side you'll see a lot of people and hear some road noise once you near Skyline.
Last time I hiked Windy Hill it was pushing 90 degrees, sunny and calm as I scaled the totally exposed Spring Ridge Trail. I was hot and sweaty and wish I did the reverse loop. This time it was pushing 40 and windy and raining and I started by dropping down Razorback Ridge with frozen extremities. Learn from my mistakes. If it's warm, start up on Skyline and drop down the exposed Spring Ridge Trail. This way you'll huff and puff your way up the cooler, shaded Hamm's Gulch Trail. If it's cool, hike up Spring Ridge instead.
There are two Windy Hill parking spots on Skyline. For this particular hike I parked at the southernmost spot. Then I took Lost Trail > Razorback Ridge Trail > Eagle Trail > Hamms Gulch Trail back up to Skyline.
This is one of those great "workout" hikes. In fact, I ran across a lot of locals in running shoes either trail running or just hoofing it up to Skyline. The trails are in good shape. You can start this hike from the bottom off Alpine Road at Hamms Gulch Trail or from the top, like I did, at Skyline, down Razorback Ridge Trail. It's called Windy Hill for a reason. Pack layers. There are picnic benches and bathrooms located at the Skyline parking lot.
My sister, boyfriend and I hiked the dirt trail 3.7 miles from the Portola Road parking lot up to the Windy Hill Summit! It was long, but worth it (7.4m round trip). We loved the sun, cool breeze, and panoramic views of the bay area leading up to the peak. I'd rate this hike difficulty as medium.
The trails are dog and horse friendly and we encountered many cute puppies and some horse poop but no horses. Many people do not clean the poop off the trails so remember to look down when you are hiking to avoid a stinky situation. It was hot and we enjoyed the shade and trees at the beginning of the trail. There is a steeper stretch in the middle of the trail with no shade but it passes quickly. Don't forget to bring water, especially if its a hot day.
Unfortunately, halfway on the trail my sister had to run back to the trailhead and parking lot to use the bathroom. She ended up getting an extra workout and running back to meet us (there is cell service on most of this trail so we could call and text each other). Her bathroom experience included sharing the toilet with flies but there was toilet paper and hand sanitizer. Visited on Mar 08, 2014