At first glance Sacramento appears to be just another mid-sized city with new restaurants, a new arena, and new apartments. However, visitors may not realize that underneath the urban renewal-era buildings, concrete malls, and bustling sidewalks exists a different world—a window into Sacramento’s past.
The winter of 1861-1862 is one of legend in Sacramento. Heavy snowfall in the Sierras followed by unprecedented levels of warmer rains caused increased snowmelt that poured into the American River. In the early morning on December 9, 1861 the American River broke through the levee and water flooded the city, sweeping away railroads and turning buildings and homes into debris. Three more floods would inundate the city before the winter was over, with the worst coming one month later on January 9, 1862. The flood waters rose so high that Governor Leland Stanford had to enter his mansion on the second floor and could only get there by boat.
While many outsiders called to abandon the city, Sacramentans stood resolute in their determination to find a way to survive in the current location. City leaders came up with an interesting solution: if Sacramento was in a flood plain, then they simply had to make higher ground. The next 15 years were spent raising city streets and sidewalks roughly 10 feet above their original level. Property owners were directed to build brick walls along the street in front of their property as the city filled the walled in streets with sand, dirt, gravel, and other excavations from the rivers. After the fill had settled, the streets were cobbled and property owners were faced with the task of either raising their buildings to the new street level or turning their first floor into a basement and creating an entrance on the second floor. As one can imagine, this was no easy task. The entire process took 15 years and was done with modest tools and small teams of horses and wagons. As Jonathan Mendick noted in a Sacramento Press article on May 26, 2010, Sacramento is the only city in California and the first on the West Coast to undertake such a project.
As Sacramentans moved up one story, the old city remained below. The spaces under the sidewalks remained unfilled, creating tunnels and passageways between buildings on the same block. While some tunnels have since been filled in due to new construction, a portion of them still exist on the west end of the city. Small skylights scattered around the sidewalks of J and K Street give small glimpses into the Sacramento underground. As you walk down the street look for the pinkish, square skylights in the sidewalk. You can also see evidence of the raised streets as you walk through Old Sacramento State Historic Park. A handful of buildings still have their entrance on the original first floor and require you to walk down stairs from the sidewalk to enter. Other buildings moved the entrance to the second floor but only for you to walk downstairs as soon as you enter. For a more in depth experience with the tunnels you can take one of the Underground Tours given by the Sacramento History Museum or join the Old Sacramento Walking Tour at the 2018 OAH Annual Meeting, April 12–14.
Meagan Olson is a Public History MA student at California State University, Sacramento.
 William M. Holden, Sacramento: Excursions Into Its History and Natural World (Fair Oaks: Two Rivers Publishing Co., 1988), 199.
 Peter J. Hayes, ed., The Lower American River: Prehistory to Parkway (Carmichael: The American River Natural History Association, 2005), 65-67.
 Holden, Sacramento, 201.
 Hayes, The Lower American River, 68.
 Holden, Sacramento, 211-213
 Holden, Sacramento, 216