From the plaque:
This was the site of Webster's
Sugar Loaf House, well-known stopping place during the
Comstock rush. Beginning in April 1860, it was used as
a remount station of the Central Overland Pony Express,
and in 1861 it became a horse change station for pioneer
stage companies and the Overland Mail.
Plaque placed by the California State Park Commission in cooperation with the Highway 50 Association and the Central Overland Pony Express Trail Association, April 3, 1960.