Friday, March 9, 2018

Tunnels: Glenwood (Tunnel 3)

The South Pacific Coast Railroad wore its audacity on its sleeve. When they first began surveying potential routes to connect San José and Santa Cruz, one of their last choices was to bring it into the San Lorenzo Valley. Initial plans had drawn the route down Soquel Creek from a location near Laurel. But surprisingly, it was Frederick A. Hihn, the owner of much of the Soquel watershed, that proposed cutting through to the San Lorenzo Valley. This, in effect, meant that the railroad would have to pass through not one but two mile-long tunnels before it could make its way to Santa Cruz. While the history of the Summit Tunnel (Tunnel 2) is well known, much less is known about the construction of Tunnel 3, which would connect the Soquel headwaters with the hamlet of Glenwood. Although the tunnel never had an official name other than Tunnel 3 (Tunnel 2 after standard-gauging was completed in 1909), it picked up the local name "Glenwood Tunnel" because it passed under the Glenwood Highway, which was completed in 1920.

Looking out the Glenwood Tunnel toward Laurel, c. 1905. [Santa Cruz Museum of Art & History]
Construction began on the wood-timbered narrow-gauge tunnel in May 1879, after grading crews had already built the right-of-way between the eastern portal of the Summit Tunnel and the hamlet of Highland above Soquel Creek. Since the tunnel did not pass through any major fault line and did not include natural gas deposits, it experienced none of the problems of the Summit Tunnel. Two crews worked on the tunnel, one from either side. Those working in the Bean Creek area were able to camp in Glenwood, probably in the large meadow beside Charles C. Martin's property, while those working at the Highland end probably shared a camp with the Summit Tunnel workers. The firm Martin, Ballard & Ferguson was responsible for both tunnels. The material encountered by the boring crews was almost solid granite, which required major explosives but also meant that cave-ins were rarely a threat. Indeed, much of the interior of the tunnel did not require timberwork because the interior walls were so solid. Wood portals were installed on both sides of the tunnel.

The town of Laurel with the Glenwood Tunnel visible in the background, c. 1905. [Whole Mountain Source Book]
Once completed in December 1879, the Glenwood Tunnel measured 5,793-feet (1.1 miles) and was the second longest tunnel after the Summit Tunnel. Railroad operations began officially in May 1880, at which point the tunnel saw regular use by South Pacific Coast trains. There is not much that can be said about the tunnel for the next thirty years. It survived the 1906 San Francisco earthquake with minimal damage due to its solid granite interior and the tunnel experienced no known upgrades until 1907, when the line was standard-gauged. Indeed, through service to Laurel from Glenwood continued until mid-1907, when the tunnel was closed for these upgrades.

Colorized postcard of the western portal of the Glenwood Tunnel with a train passing through, c. 1910. [Ken Lorenzen]
Upgrading of the tunnel was relatively straight-forward, but it did entail one detail that the previous tunnel had not: a road above the eastern portal. Although the Glenwood Highway was not completed for over another decade, traffic down what would become that highway arrived earlier. Before 1907, traffic crossed Bean Creek just to the north, but the new tunnel was designed so the road could go directly over the tunnel. On both sides, the wooden portals were replaced with solid concrete faces. At Laurel, the portal only extended about 20 feet into the hillside before the concrete was replaced with redwood timber. Because a natural spring emptied into the tunnel at this end, the railroad installed a pipe that led to a water cistern which was kept above the portal. A small dirt road was built to access this cistern, and it may have continued further behind the tunnel since the hillside was not overly steep here. 

Looking through the Glenwood Tunnel toward Glenwood, c. 1920. [George Pepper]
On the Glenwood side, the concrete portal also only extended about 20 feet so that it could support the road that ran immediately above it. At this time, the road was still gravel, but it would later be paved and repurposed for automobile traffic. On both sides, a metal railing was placed roughly three feet high above the portals to keep pedestrians and vehicles from falling onto the tracks. Within the tunnel, the granite was dynamited further to expand tunnel to support standard-gauge trains. The construction work was completed in March 1909, after which the line reopened to through traffic between Santa Cruz and Los Gatos.

A parade over the Glenwood Tunnel's east portal, c. 1915. Note the road is not yet paved and the lack of automobiles.
As before, the Glenwood Tunnel lived on for another thirty-five years without any issues. As automobile traffic increased, the trains that passed through the tunnel decreased. Glenwood ceased its life as a tourist destination in 1924 and the F.A. Hihn Company left Laurel around 1914. When the winter storm of February 26, 1940 damaged large portions of the right-of-way, Southern Pacific Railroad decided to shut down operations along the line. Throughout 1941, tracks and ties were removed from the right-of-way. A short-lived campaign in January 1941 led by community members suggested converting the tunnel into a one-way road for local traffic to allow people to travel between Laurel and Glenwood, but the project was deemed expensive and unfeasible. In April 1942, the demolition firm H. A. Christie & Sons dynamited the portals on either side, protecting them for future use while sealing them for insurance purposes. On the Laurel side, the railroad ensured that access to the natural spring was maintained, while at Glenwood, heavy steel girders were installed under Glenwood Highway to insure it did not collapse the road in the explosion. Access to the spring was eventually blocked by movements caused by the 1989 Loma Prieta Earthquake.

Southern Pacific photograph of Glenwood Tunnel's west portal after the February winter storm, 1940. [Bruce MacGregor]
Geo-Coordinates & Access Rights:
West Portal: 37.117˚N, 121.968˚W
East Portal: 37.110˚N, 121.986˚W

The west portal of the Glenwood Tunnel is still easily accessed. Explorers can venture down to the Laurel townsite off State Route 17. The portal is located directly opposite the beginning of Redwood Lodge Road down a dirt driveway that parallels a home on the south side. It should be visible from the Laurel Road/Schulties Road intersection. The top of the concrete portal is fully exposed and can be walked upon, while the interior is mostly collapsed now. The old piping for the water, in use until 1989, remains in place beside the tunnel. The former road that once ran over the portal is no longer intact and run-off has now eroded the hillside behind the tunnel significantly, exposing much of the concrete ceiling, which can be viewed atop the portal.

Western portal of the Glenwood Tunnel at Laurel, showing the extended face and the remains of the water system. [Derek R. Whaley]
The east portal of the Glenwood Tunnel is easier to find but more difficult to practically access. Driving on Glenwood Road from Scotts Valley, stop at the wagon wheel plaque that tells the history of Glenwood. Walk down the road until it turns sharply to the west. The portal is directly beneath the road at this point (look for the metal railing). Accessing the tunnel requires climbing down into a steep gully (the former right-of-way) that is filled with poison oak. It is impossible to obtain a good photograph of the tunnel due to the abundance of vegetation which blocks the view. The tunnel is collapsed almost immediately at the entrance and there is very little to investigate here.

The eastern portal of the Glenwood Tunnel, as viewed from Glenwood Road. [Derek R. Whaley]
Citations & Credits:


  1. I wonder who owns the tunnel, and what conditions must exist in order to reopen this one item? I'm well aware that just reaching this location would be the bigger difficulty.

  2. Take a look at the rare crossing bell from the photo Bruce MacGregor supplied from the Roy Blair Collection. The only one like this I ever saw in person was out on the old Southern Pacific main line in the Colma cemetaries. This is now long gone, the right of way replaced by BART. Outside of Los Gatos and Santa Cruz, the only crossing signals through the Santa Cruz Mountains I am aware of were this one at Laurel and wigwags at Aldercroft and the crossing at Highway 9 north of Santa Cruz.


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