US 466 – Polonio Pass and Antelope Grade

US 466
Polonio Pass and Antelope Grade
El. 1750′

Original pavement along the route in 1998.
Numerous curves along the old alignment in 2019.
Old wooden railing along Polonio Grade
Looking west toward Parkfield Junction from the old alignment
Down the grade toward Parkfield Junction and the San Andreas Fault.
Striping and old paving
Along the grade with both alignments visible.

Polonio Pass is the second of two passes US 466 over through the Coast Ranges. In the late 1950’s, a major realignment was undertaken to straighten the roadway and add passing lanes. A significant portion of the original alignment remains intact today and driveable for most vehicles. Wooden railing and some striping still remain on the crumbling pavement.

Go West on US 466 to Shandon

Go East on US 466 to Famoso

Return to the US 466 Introduction

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