Slan is an SF novel by A. E. van Vogt as well as the name of the fictional race of superbeings featured in the novel. In 2016, Slan was awarded the Retro-Hugo Award for Best Novel for 1941.
This series of caches is themed around some of the great science fiction novels. It will take you along parts of the Alpine Trail and the extension along Sand Hill Road in Portola Valley.
Please replace as found and beware of muggles. This area can be quite busy at times. Cycling and hiking the trail are good choices. I suggest parking along Oak Avenue as a reasonable place to park. You need to cross the road but there is a traffic light. From there, the trail will take you to this cache and other nearby ones.