History of Transportation in Cuesta Pass; El Camino Real, Southern Pacific Railroad and US Route 101

Cuesta Pass (locally known as the Cuesta Grade) and the associated Cuesta Grade along US Route 101 roughly consists of a 8 mile segment of expressway from California State Route 58 near Santa Margarita south to CA 1 in San Luis Obipso.  Cuesta Pass is a low mountain pass of the Santa Lucia Range which lies at 1,522 feet above sea level.  Cuesta Pass can be found at Post Mile SLO 35.132 on US 101.

Chapter 1; the History of Cuesta Pass

Cuesta Pass was a long known way through Santa Lucia Range between the coastal areas near San Luis Obispo north into the Salinas River Valley by the local Chumash Tribes of Southern California.  During September of 1769 Portola Expedition of Las Californias the Spanish actually missed Cuesta Pass and opted to attempt to travel up the coast through the Big Sur Region.  The Portola Expedition ultimately found the terrain impassable at Ragged Point and traveled northeast up San Carpoforo Creek to San Antonio Valley near modern day Jolon.  The Spanish didn't discover Cuesta Pass until it was located during a 1774 expedition by Juan Bautista de Anza.  The route over Cuesta Pass was solidified by the Second Expedition by Juan Bautista de Anza in 1775-1776.   The route of the expeditions led by Juan Bautista de Anza solidified what would become the route of El Camino Real (The Royal Road).

The route of El Camino Real was intended to solidify a path of travel between the Catholic Missions of Las Californias.  In 1804 Alta California was formed out of the larger Las Californias.    El Camino Real would ultimately connect 21 Catholic Missions of Alta California ranging approximately 600 miles spanning from Mission San Diego de Alcala in San Diego north to Mission San Francisco Solano in Sonoma.  The Missions of El Camino Real were established from 1769 through 1823.  In the case of Mission San Francisco Solano it was established two years after Mexico had won it's independence from Spain in 1821.  Each Mission was meant to be approximately 30 miles apart from each other which would require a single day of travel by horseback.

Mission San Luis Obispo de Tolosa was the fifth to be established along the path of El Camino Real in 1772.  Following the expeditions of Juan Bautista de Anza the route north from Mission San Luis Obispo de Tolosa was known as the "Padre Trail.".  Following the secularization of Mission San Luis Obispo de Tolosa (as well as the other Missions) in August of 1833 the land holdings were split off into Ranchos.  Despite El Camino Real functionally no longer existing the route up the Padre Trail through Cuesta Pass remained a popular.  The City of San Luis Obispo quickly grew around the former land holdings of Mission San Luis Obispo de Tolosa.  Alta California was annexed by the United States in early 1848 and San Luis Opispo became the first incorporated City in the newly formed San Luis Obispo County in 1850.  Cuesta Pass and the Padre Trail from San Luis Obispo north to Rancho Santa Margarita are clearly seen on this 1857 Britton & Rey Road Map of California. 

According to Rider Magazine the City of San Luis Obispo funded construction of a new wagon road up Cuesta Pass to replace the Padre Trail.   The new wagon road was constructed in 1876 by Chinese Laborers up the western flank of Cuesta Pass and was initially known as Mountain Road.  In modern times the 1876 Mountain Road is still maintained as Old Stagecoach Road.  Old Stagecoach Road while an improvement over the Padre Trail still featured a 15% maximum grade.

Rider Magazine; a short history of Cuesta Pass

By 1889 a new rail siding of the Southern Pacific Railroad known as Santa Margarita was established near the top of Cuesta Pass.  Santa Margarita quickly grew as it was the temporary terminus of the new Southern Pacific Line between San Francisco and San Diego due to the proximity to the Mountain Road.  The Southern Pacific Line down Cuesta Pass wouldn't be open until 1894 and was completed to San Diego by 1897.  While the Southern Pacific Line is somewhat close to the alignment of Mountain Road it takes a massive outward western swing to maintain the grade getting there. 

In 1904 the American El Camino Real Association was formed with the goal to mark a modern highway that corresponded to the historical route between the Spanish Missions.  Ultimately the path of American El Camino Real was to be marked by the signature bells the corridor is known by today.  The first bell marking the American El Camino Real was placed in 1906 and it is estimated by 1915 that there may have been anywhere to 158 to 400 placed in-field.  Cuesta Pass and the Mountain Road being the main highway at the time was signed as part of the American El Camino Real.  The American El Camino Real was one of the earliest analogs of what would become the signed Auto Trails.  The background of the American El Camino Real is covered extensively on CAhighways.org.

CAhighyways.org on the American El Camino Real

The era of State Highway Maintenance through Cuesta Pass would ultimately begin with the 1909 First State Highway Bond Act which was approved by voters in 1910.  One of the highways approved through the 1909 First State Highway Bond Act was a 481.8 mile highway originating at the City Limits of San Francisco which terminated in San Diego.  This highway would ultimately come to be known in time as Legislative Route Number 2.

CAhighways.org Highway Chronology Chapter 1; Early State Highway Era

According to Historic101.com construction of the LRN 2 over Cuesta Pass began in 1912 and was completed by 1915 according to Rider Magazine.  The original path of LRN 2 snaked northward through Cuesta Pass on an alignment which largely utilized it's eastern flank.  LRN 2 was ultimately paved with a 15 foot wide concrete road base by 1923 which was much akin to similar State projects such as the original Ridge Route or San Juan Grade.  This alignment of LRN 2 would ultimately become part of US Route 101 when the US Route System was created in November of 1926. 

Historic101.com Cuesta Home Page

Of note; El Camino Real over Cuesta Pass was joined by the Pacific Highway in 1913.  Both El Camino Real and Pacific Highway can be seen on this 1920 Clauson Company Road Map of California utilizing LRN 2 on Cuesta Pass.

The early alignment of LRN 2 over Cuesta Pass can be seen in an unpaved configuration in this photo below from an unknown date in the 1910s.

The same location atop Cuesta Pass can be seen paved with concrete in this 1922 photo.

This photo of Cuesta Pass is dated from 1923.

Below in this 1930 photo a sharp curve paved in concrete can be seen snaking through Cuesta Pass.

The 1912 alignment of LRN 2 over Cuesta Pass was still in use by US 101 by the mid-1930s.  This 1935 California Division of Highways Map of San Luis Opispo County shows the 1912 alignment of LRN 2 in great detail.

According to Rider Magazine US 101/LRN 2 was straightened through Cuesta Pass onto a grade similar to the modern highway by 1938.  This undated photo from the late 1930s shows the straightened US 101/LRN 2 grade which appears as a close analog to the modern expressway.

A major change to US 101/LRN 2 through Cuesta Pass when the highway was realigned on a more direct route which bypassed Santa Margarita.  This change can be seen by comparing the 1956 State Highway Map to the 1957 Edition.

In 1964 the hidden Legislative Route Numbers were dropping during the California State Highway Renumbering.  The latest change to US 101 through Cuesta Pass came in 2004 when the highway was expanded from four lanes to six. 


Chapter 2; Mapping out the alignments over Cuesta Pass

Much like the previous blog regarding the Ridge Route one of my goals was to map out the historical alignments of transportation over Cuesta Pass.  Despite Cuesta Pass being somewhat small in scale in terms of a mountain pass there are five notable transportation corridors which can be presently found.  On the map below the following color codes correspond to various vintages of transportation:

Yellow:  Denotes the present alignment of US Route 101 over Cuesta Pass.

Blue:  Denotes what remains of the 1912-1915 path of LRN 2 and early US 101 over Cuesta Pass.

Red:  Denotes the 1876 Mountain Road over Cuesta Pass which is presently signed as Old Stagecoach Road.

Purple:  Denotes where the 1774 path of El Camino Real over Cuesta Pass can be found on what is left of the Padre Trail.

Grey:  Denotes the path of the 1894 Southern Pacific Railroad over Cuesta Pass.

Chapter 3; driving modern US Route 101 over Cuesta Pass from CA 58 south to CA 1

My approach to the modern descent on US 101 south over Cuesta Pass was from CA 58 west from Santa Margarita.  CA 58 has a western terminus on El Camino Real which utilizes the pre-1956 alignment of US 101.

From the west terminus of CA 58 the route of US 101 south is shown 8 miles away from San Luis Obispo.

US 101 south approaching Cuesta Pass quickly drops to an expressway grade at Tassajara Creek Road.

Approaching Cuesta Pass US 101 south is signed as a Safety Corridor.  Even the modern alignment of US 101 over Cuesta Pass is known for a high rate of accidents amid it's peak grade of 7%.

South of an unnamed gated roadway traffic on US 101 is advised of an upcoming brake check area.

US 101 south crosses over a bridge which directs pedestrian/bike traffic onto a former segment of the 1912-1915 alignment of LRN 2 on Cuesta Springs Road.

US 101 south intersects Cuesta Springs Road at the Cuesta Pass brake check area.  The brake check area also serves as access the 1876 Old Stagecoach Road.

US 101 south begins to rapidly descend from Cuesta Pass.  Much of the modern alignment of US 101 was directly cut through the 1912-1915 alignment of LRN 2 when the roadway was expanded to an expressway in 1938.  In the emergency parking area on the southward descent a El Camino Real bell is posted.

Much of the remaining concrete portion of the 1912-1915 alignment of LRN 2 is located immediately south of the emergency parking area.  The 1912-1915 alignment would have crossed the modern US 101 expressway and another remaining segment can be found alongside the northbound lanes.

US 101 south continues to descend and has an intersection with the bottom of Old Stagecoach Road.

US 101 south enters the City of San Luis Obispo and is signed as the Purple Heart Trail.  Within San Luis Obispo US 101 south becomes a freeway.

At Exit 204 US 101 south intersects it's former surface alignment on Monterey Street.

The grade of Cuesta Pass on modern US 101 ends Exit 203B where CA 1 begins to multiplex the freeway.

Chapter 4; driving the 1876 Old Stagecoach Road, finding the remains of the 1912-1915 alignment of LRN 2 and the Padre Trail

After driving the modern grade of US 101 through Cuesta Pass I backtracked to the top so I could drive the 1876 Old Stagecoach Road.  I made the descent down Cuesta Pass on US 101 and began my drive uphill from the bottom of Old Stagecoach Road.  Almost immediately traffic on Old Stagecoach Road is greeted with a concrete surface.

Very quickly there is a split in Old Stagecoach Road from the 1912-1915 alignment of LRN 2.  The concrete surface splits off to the right and judging by the conditions probably is the original pavement that was poured in 1923. Old Stagecoach Road splits left and continues uphill towards Cuesta Pass.

Old Stagecoach Road drops to a dirt surface and enters a heavily wooded area.  Traffic is advised that the remaining 2.3 miles to the top of Cuesta Pass is within private property.  Old Stagecoach Road despite being an active public road is also frequently used as a hiking trail.

Old Stagecoach Road is relatively flat until it intersects the Padre Trail at an unmarked gate.

Old Stagecoach Road narrows and begins to climb rapidly towards Cuesta Pass.  This part of Old Stagecoach Road is wide enough for only a single vehicle and has a maximum grade of 15%.  The modern grade of US 101 can be seen off to the east throughout much of the climb.

In places on Old Stagecoach Road the 1912-1915 alignment of LRN 2 can be seen above the modern alignment of US 101.  As noted above the 1938 realignment of US 101/LRN 2 made a massive cut through the previous alignment which straightened most of the curves.

Old Stagecoach Road finally climbs to US 101 and meets Los Padres National Forest Route 29S11.

From the very top of Old Stagecoach Road the peak of the Padre Trail can be found off to the right of asphalt.

From the top of Old Stagecoach Road there is a monument dedicated to the 2004 rebuild of US 101 over Cuesta Pass.  From the monument the modern grade of US 101 stands in stark contrast to the Padre Trail.  It is quite odd to see a wagon road used by the Spanish on El Camino Real next to a modern highway.