During spring, various East Bay hills come alive in waves of greenery. The East Shore Loop to Lake Del Valle has been very popular in the Bay Area Hikers Facebook group this year.
https://www.alltrails.com/trail/us/california/east-shore-loop-to-lake-del-valle
I live about 10 miles from the trail head and this 20 mile out and back is my regular bicycle ride through the Vineyards. I finally made the hike from the trailhead today and it is absolutely worth it.
Parking is gone by about 7am usually, so either go at 11:30am or park at Sycamore Park about half mile down the road and walk up. If you live in the East Bay, biking to the trailhead is definitely a great option.
The first mile of the trail is somewhat steep and gains about 600 feet. It is a moderately difficult hike but it is definitely one of the best bang-for-the-buck hikes in the East Bay during Spring.
The trail is packed and crowded, so that’s the downside.
I have been waiting to do the backpacking trip from Del Valle to Mission Peak (or Sunol), this hike has motivated me to consider that seriously.