photo by Flickr user Mathesont
From the City of Walnut Creek webpage:
Join Mayor Bob Simmons at 8:30 a.m. Saturday, June 9 for a walk in the Shell Ridge Open Space and learn how Shell Ridge got its name. Meet at the Marshall Drive entrance by Indian Valley Elementary School for an 8:30 a.m. departure (Note earlier start time!) This is a 3.5 mile walk on both fire roads and single-track trails with about 400′ of elevation change, and will last about 2 hours. Please bring water and wear a hat, clothing to protect against the sun. Don’t forget the sunscreen!