Santa Clara

Quicksilver Prospecting


Established by the Spanish in the 1840′s, the New Almaden Quicksilver mines produced cinnabar, the raw ore from which mercury is extracted. New Almaden served as a productive mining center for twelve decades through Spanish, Mexican, and US rule. Hit a series of key shafts and tunnels then report back to the Mine Office and Map House at English Town.
11.3 MI
Insertion: Hacienda Trail, New Almaden, CA

Map of Quicksilver Prospecting
A route through the cinnabar mines at New Almaden

Google Map


New Almaden is the longest running, most profitable mining operation in California history. The Ohlone Indians, who themselves had collected cinnabar from the region for thousands of years, revealed the deposits to the Spanish, who began their own mining operation in 1846. During the California Gold Rush, mining accelerated to a feverish pace and ultimately changed from Spanish to American hands. The Quicksilver Mining Company assumed operations in 1864. Mercury is useful as an agent in gold mining and, tellingly, New Almaden generated more wealth during the California Gold Rush than gold itself.

In 1927, the New Almaden mine finally ceased operations and remained dormant until the late 1930s. But, the Second World War has once again introduced the urgent need for mercury, this time for the manufacture of munitions.

To assist in the war effort, the New Almaden Company has resumed operations, building several new mining offices (including one at English Town) and the Gould Rotary Furnace in an effort to modernize and produce more ore at a lower cost. Many of the mines date to the 1880s and 90s and the region is largely depleted. Nevertheless, your job is to survey a collection of these sites and report back to the mining office at English Town.


Your route begins at the north trail head on Hacienda Trail.

Buena Vista Pumphouse

The Buena Vista Pumphouse operated from 1882 – 1893 and has laid in ruins for some time. Even while in operation, it never produced much ore; it’s main role was to pump water out of other (more productive) tunnels.

Santa Isabel Shaft

The Santa Isabel Shaft commenced operation in 1877 and was a prolific producer of ore. However, by 1894 it was depleted and converted to supply carbonic acid gas for the budding dry ice industry.

Trail to the April Trestle

In the valley below, the abandoned St. George Shaft is just visible. Circa 1887, this shaft was fully operational and surrounded by Kempville, a small cluster of miner’s cottages.

April Trestle

The April Trestle carted ore from St. George Shaft to the furnaces at the Hacienda, the center of mining operations for New Almaden during the late 1800s.

Powder House

First built in 1866, the Powder House served as a store house for mining explosives.

San Christobal Mine

San Christobal remains in very good condition; it’s entrance and immediate interior are still accessible.

Catherine Tunnel

A short distance from Bull Run, a once popular picnic area during New Almaden’s hay day, is the Catherine Tunnel. Long since abandoned, the tunnel is collapsed today.

Rotary Furnace

More than anything, it is H.W. Gould’s 1939 invention, the Rotary Furnace, that gives hope to the renewed effort at New Almaden in the face of World War 2. The Rotary Furnace is able to refine ore much faster and on site. The end results of the installation are sealed flasks of mercury ready for shipment.

Miners’ House

A lone residence remains on the site long known as Spanish Town.

Spanish Town

The site at Spanish Town dates to the 1850s and served as the original (Spanish) hub of operations at New Almaden. It borders some of the most productive mines in the area.

Hidalgo Cemetery

One of the few remaining features of Spanish Town, Hidalgo cemetery is now empty of graves.

The Main Tunnel

The Main Tunnel is the original New Almaden mine. This is where the Spanish first discovered Cinnabar in the region (guided by the Ohlone) and was the nexus of the original Spanish mining operation at New Almaden.

Yellow Kid Tunnel

From 1894 to 1896, Yellow Kid was the most productive operation at New Almaden.

Mine Office and Map House at English Town

Cornish miners first established English Town in the 1860s, and it remained an important operational and domestic center for the life of New Almaden. Once you visit the Mine Office and Map House (built to renew mining operations in the wake of World War 2), return to your starting point on the Hacienda Trail.