Entry No. 3 — the Sacramento file — filed under: hidden tunnels
Sacramento Underground Tours (Sacramento History Museum)
After ruinous floods in the 1860s, Sacramento didn't move — it jacked its own street grade up roughly ten feet and kept building on top of the original ground floors. The museum's hour-long tour drops you through a trapdoor into the hollow sidewalks and buried storefronts left underneath Old Sacramento's boardwalks, a space local lore also links to old opium dens and brothels.
The story
In the early 1860s, a sequence of ruinous floods repeatedly submerged Sacramento under feet of river water. Rather than abandoning the Gold Rush boomtown, property owners and city leaders hatched an audacious fix: they decided to physically elevate the entire city. Over the course of a decade, workers raised street grades by roughly ten feet using brick retaining walls, thousands of wagonloads of dirt, and elevated wooden boardwalks, effectively burying the original ground floors of Old Sacramento alive.
The spaces left behind became a shadow grid beneath the elevated sidewalks. Down in the damp, windowless foundations, city life continued out of sight—a subterranean realm that local lore quickly tied to back-room gambling, opium dens, and brothels operating below the respectable streetscape. Descending through a trapdoor from the Sacramento History Museum places you right inside that swallowed city, where original brick facades, buried doorways, and hollow sidewalk vaults sit quiet beneath the modern foot traffic above.
What it's like
You'll gather inside the Sacramento History Museum at 101 I Street before your guide leads you out of the display rooms and down into the foundation spaces. Groups are capped at 20 people per tour, so reserve your spot in advance rather than chancing a walk-up. Closed-toe shoes are strictly required for navigating the dusty, uneven subterranean paths, and you'll need to keep your phone tucked away—photography is prohibited down in the underground. The walk lasts about an hour and covers roughly a half-mile, ending with a stroll back along the raised boardwalks so you can visually map the subterranean rooms against the modern street level.
The move: Book the underground tour together (closed-toe shoes required, no photos allowed down there), then walk the raised boardwalks above the actual rooms you just stood in and compare street level to basement level.
- 📍 Old Sacramento
- 💸 $$
- ⚡ Up for anything
- 🌗 Indoors
Where: 101 I Street, Sacramento, CA 95814
Hours: Added 2026-07-20 — confirm current hours before you go.
⚠ Seasonal or scheduled — always check before you go.
Pair it with
- Delta King — Walk two minutes from the buried 1860s storefronts to step aboard this real 1927 sternwheeler riverboat docked on the riverfront.
- Hawthorne's Hideout — Continue your subterranean tour of Old Sacramento by finding the hidden door beneath Stage Nine to reach this underground speakeasy.
- Garden of Enchantment — Pop off the raised boardwalks into this 1986 Old Sacramento shop packed with Wiccan supplies, wind chimes, and hand-carved statuary.
Good to know
Are photos allowed during the tour?
No. Photography and video recording are strictly prohibited once you step below street level.
What footwear do I need?
Closed-toe shoes are mandatory due to the uneven surfaces, dirt paths, and historic structures underground.
How long is the tour and where does it meet?
The tour runs for approximately one hour, covers roughly a half-mile of walking, and begins inside the Sacramento History Museum.
Why was Sacramento built over its old streets?
After catastrophic flooding in the 1860s, the city raised its street grid by about ten feet, leaving the original first floors buried as basement vaults and hollow sidewalks.
Plan a visit & invite your people →
Further reading: Official site · hauntedplaces.org · visitcalifornia.com · Reddit
last checked: 2026-07-20