Category Archives: SR-126

Original pavement remaining at Castaic Junction, CA on old US 99

Castaic Junction, located just north of Six Flags Magic Mountain in the Santa Clarita Valley was an important stop along US 99 and State 126 until the 1980’s. A Standard Oil gas station, one of the largest and busiest at the time, was located here in addition to Tip’s Restaurant. The restaurant was reported to be the last stop for James Dean before he died on September 30, 1955. A Beacon station also existed here at the south side of the junction, though it didn’t last as long as the Standard station. The gas station closed sometime in the 1980’s and the restaurant persisted as the Castaic Junction restaurant a bit longer.

A Brief History of the Roadway Changes

Map of the original version of Castaic Junction before the 1948 widening.
1944 view of Castaic Junction looking southerly. SR-126 enters from the right. Courtesy – Caltrans

The roadway through the junction has also undergone many changes since it was first paved. In 1917, a 15′ concrete slab was laid down. This was widened in 1922 by adding two 2.5′ slabs on either side of the existing concrete. At the time, Castaic Junction was a “wye” intersection, with US 99 making up the east side and State 126 on the south side. The west side was a connector road from SB US 99 to WB 126. In 1931, the 1917/1922 pavement was removed and replaced with a wider two-lane section along the same route. By 1933, an additional lane was added making it a three-lane “suicide lane” setup.

Looking northerly at Castaic Junction in 1948 just after widening. Photo Courtesy – Caltrans

In 1948, yet more changes were made to the junction. US 99 was realigned a bit to the east and made a four-lane expressway. State 126 was also widened, though just at the junction itself. The former west leg of the junction was removed as the Standard Oil gas station was augmented. This configuration lasted until 1964 when I-5 was constructed and the whole intersection was bypassed.

1969 aerial photo showing the 126 Freeway and I-5 Freeway adjacent to the original Castaic Junction. Courtesy – Caltrans

Today, little remains of any of the structures that existed at the junction. A new shopping center and Caltrans maintenance yard occupy the area east of the junction. The original traffic signals were replaced and additional curbs were added.

Surprisingly, the original 1917 wye junction remains nearly completely intact. The west and east legs of the junction are still visible, despite a major realignment, the construction of the Standard Oil gas station in 1948, and its subsequent demolition. How long any of this will last is unknown as development is likely to erase these traces in the near future.

Further Reading:

US 99 – Castaic Junction

Current photos of the intersection

Aerial view of Castaic Junction from May 2022. Black lines denote remaining wye intersection. Courtesy – Google Earth
Looking north toward the west leg of the wye. The slight rise and banking can be seen here to the left.
Looking north along the west leg of the wye intersection. Pavement still visible after all these years.
Southerly view along the west leg of the wye. This is roughly where the east and west legs merged.
South end of the east leg of the wye. The lines of plants are 10 feet apart, making this the 1931 paving, likely the southbound lane.

Image of the Week – 3/15/15

Interstate 5 under construction at Magic Mountain Parkway in 1964.
Interstate 5 under construction at Magic Mountain Parkway and the Santa Clara River in 1964. Old US 99 is visible on the right side.