Nestled in the Carrizo Gorge in San Diego County, California, the Goat Canyon Trestle Bridge stands tall and proud. It is one of many unique wonders of the gorge, giving the railway that runs through it the name 'Impossible Railroad'. There's a lot of cool information about this area, and we're going to explore just some of it as we tell you all about the world's largest wooden trestle bridge and the canyon it crosses.
Goat Canyon Trestle Bridge is the largest all-wood trestle bridge in the world. When construction finished in 1933, it replaced a collapsed tunnel on the San Diego and Eastern Arizona Railway. The railway, now defunct, is part of the Anzo-Borrego Desert State Park. Since ending operations, the entire railroad is a popular hiking spot, though parts of it rest on private property. Most hikers find access through De Anza Spring Resort and the Jacumba Valley.
The bridge is over 600 feet long and almost 200 feet tall, and its unique construction is due to a number of factors. First, the temperatures in the canyon vary greatly, and this was cause for concern when considering building materials. Extreme temperature fluctuations could cause metal fatigue, resulting in collapse. Instead, builders used redwood pine, which could better withstand these fluctuations. Carl Eichenlaub, the Chief Engineer of the railroad, designed the bridge to meet all of these conditions, including setting the bridge at a 14-degree curve to withstand the heavy winds in the canyon. Additionally, builders used no nails to assemble the bridge. Large bolts hold the wood in place, and the bridge remains relatively sturdy, despite the collapse of other tunnels along the same route.
Engineers still had worries about the risk of fire due to the extreme temperatures and the sparks flying from the locomotives. They outfitted the bridge with water pipes and valves, connected to a large water tank on the hill above.
Builders assembled portions of the trestle in the canyon below and then lifted them into place. In all, the construction of this bridge took less time than expected. While the railroad cost 18 million and took nearly 13 years to construct, the trestle took less than 2 years and cost less than 400,000 dollars.
Construction of the impossible railroad began in 1907 and finished in 1919. This railroad was the answer to a shortage of routes to and from San Diego and provided a connecting route to the Southern Pacific Railway line. Previous to its construction, only one railway met San Diego - a route running north to south from Los Angeles. Backed by Theodore Roosevelt, this railway would provide rail passage for freight and passengers alike, running through 17 tunnels on its way through the Jacumba Mountains.
Why impossible? Engineers of the day dubbed this railway in honor of the series of seemingly impossible-to-solve logistical challenges they faced while building it. Builders had to tunnel through unstable prehistoric landslide rock. This would lead to later complications - the collapse of tunnels 7 and 15 along the route was devastating to the railway. Additionally, earthquakes, landslides, hurricanes, and fires plagued the canyon. Social and political events during and following the time of construction offered more challenges to the rail. Border skirmishes, lawsuits, World War 1, and the Great Depression all contributed to the struggles faced in building, maintaining, and running this rail. Passengers described the route as unpleasant - the smoke from the trains in the tunnels was a nuisance to riders.
The railroad was never highly successful. A series of disasters kept it in and out of service until its last ride in 2008. Shortly following, another tunnel (tunnel 6) collapsed. There are currently no plans to reopen the rail.
Avid hikers and rail fanatics find a great destination in the railway and bridge. Several trails through the Jacumba Mountains, Carrizo Wilderness, and Anzo-Borrego touch or explore this area. A number of loop trails cover much of the area, and a strenuous out-and-back trail runs along the railroad itself to the trestle bridge. This out-and-back trail passes through a series of tunnels and over many small trestle bridges.
We cannot confirm the safety or accessibility of any of these trails and suggest you do a lot of independent research before attempting a hike in the area. Other hikers advise packing a lot of water and going early in the morning. Many will also recommend the De Anza Springs resort as both a place to start your hike and a relaxing attraction to spend time at after you finish. Remember that you can only access the trail from De Anza with permission, otherwise, you're at risk of a trespassing ticket.
The rail hike from De Anza takes you past two derailed passenger train cars, both covered in graffiti. The first is mostly intact, but watch out for glass and other dangerous debris in the area surrounding the car. We advise steering clear of the second car as you pass it - a fire in the car makes it unstable. There is a lot of sharp metal and glass surrounding the second car, as well. You can also see a couple more rail cars in the valley below along the hike. Do not trespass in any of the passenger cars - you risk physical danger and trespassing violation tickets.
All hikes in the area are moderate to strenuous, with no wheelchair accessibility. Bicyclists do find some parts of the trail system adequate for rides but have to walk their bikes during several portions of the trail.
This wilderness is home to many species of animal, including one - the Peninsular bighorn sheep (Ovis canadensis cremnobates) - that doesn't exist anywhere else in the United States. This is an endangered variety of bighorn and less than 1,000 of them still exist today. Bell's vireo (Vireo bellii), an endangered songbird, also calls this area home.
Visitors can also sometimes spot Belding's savannah sparrows (Passerculus sandwichensis beldingi), California gnatcatchers (Polioptila californica californica), mountain goats (Oreamnos americanus), coast horned lizards (Phrynosoma coronatum), golden eagles (Aquila chrysaetos), and many other animals. The area also contains a lot of unique and endangered flora.
For people interested in flowers and succulents, it's a great destination. The Peninsular fishhook cactus (Mammillaria dioica), California fan palm (Washingtonia filifera), and beavertail pricklypear (Opuntia basilaris) all grow natively there. Here's a list of other fauna and flora that live in the gorge and surrounding wilderness.
This list isn't exhaustive. For more information on the various species living in the area, go to the Anzo-Borrego Desert State Park site or to iNaturalist. If you visit, be sure to be respectful. Staying on trails preserves the natural habitats of these animals and flora. It is only with our help and care that many species have a continued chance at survival. Do not pick any flowers or disturb any wildlife, especially if you are not familiar with what it is. Some of these plants are poisonous, and others are simply sensitive to disturbances outside of their biomes. Often, human interference spells disaster or extinction for many plant and animal species.
The post Discover The World's Largest Wooden Trestle Bridge appeared first on AZ Animals.