With Episode 4.05, we turn our attention to Route 10. This first episode on Route 10 starts with an exploration of the 10th route (the last ordinal route we'll do), which was the Emigrant Gap Highway, and became the basis for LRN 37. This became part of the Lincoln Highway, then US 40, and is now part of I-80 from Sacramento to Nevada. We look at LRN 10, which became Route 198 from US 101 near San Lucas to Sequoia National Park. We then explore Sign Route 10 (which we discussed in our episode on I-5 in Los Angeles county), which ran from US 101A to US 101, later becoming Route 42 and US 101 Bypass, and eventually I-105 and I-5. Lastly, we turn to post-1964 Route 10, which is today's I-10. In this episode, we focus on the first segment: "From Route 1 in Santa Monica to Route 5 near Seventh Street in Los Angeles", which is today's Santa Monica Freeway. We look at its origins as Sign Route 6, which became Sign Route 26 along LRN 173, LRN 166, and LRN 171. We focus on LRN 173 (LRN 166 and LRN 171 were discussed in our episode on I-5 in Los Angeles county, as well as our episode on Route 6), which was Olympic Blvd. We explore the history of the Santa Monica Freeway segment, the experiments tried along this highway, some significant projects along this segment, and some significant names on this segment.

We will complete our exploration of Route 10 in Episode 4.06, which explores the San Bernardino Freeway: Its origins in LRN 26 and LRN 64 and the Ramona Airline. The history and strange intertwinings of the US highways that were signed on Route 10: US 60, US 70, and US 99. The transition to I-10 and the story of Route 10S. Lastly, we'll cover projects and names on the segment.

For more information, see this episode's forever page at CARouteByRoute.org.

Episode 4.04 is our second episode exploring Route 9, which in its post-1964 version runs from Santa Cruz to Saratoga and Los Gatos. Before 1964, Route 9 continued N up to the Mountain View area, and then across to Milpitas, and up to the Castro Valley. The previous episode covered post-1964 Route 9 (and the first segment of pre-1964 Sign Route 9) from Santa Cruz to Saratoga and then into Los Gatos, as well as all the 9th State Route and LRN 9. This episode (4.04) covers the pre-1964 Route 9 portions N of Saratoga: Sign Route 9 through Mountain View, Milpitas, and up through Hayward and the Castro Valley. This portion of Sign Route 9 became Route 85, Route 237, Route 17/I-880/I-680 (in portions) and Route 238. The next pair of episodes will be covering I-10, with episode 4.05 covering the Santa Monica Freeway portion, and episode 4.06 covering the San Bernardino Freeway portion.For additional information and more links, see this episode's page on the podcast's forever home, caroutebyroute.org.

Episode 4.03 starts a pair of episodes that explore Route 9, which in its post-1964 version runs from Santa Cruz to Saratoga and Los Gatos. Before 1964, Route 9 continued N up to the Mountain View area, and then across to Milpitas, and up to the Castro Valley. This episode (4.03) covers the current Route 9 from Santa Cruz to Los Gatos; the next episode (4.04) covers the remainder of pre-1964 Sign Route 9 through Mountain View, Milpitas, and up through Hayward and the Castro Valley. This episode also explores the 9th State Route between Peanut and Kuntz (now Mad River), and LRN 9. LRN 9 ran all the way from Ventura to San Bernardino, and was Sign Route 118 from Ventura to Pasadena, and US 66 from Pasadena to San Bernardino. As always, we'll talk about historical routings, projects along the route, and some significant names. As noted, the next episode explores the remainder of pre-1964 Sign Route 9 from Saratoga through Milpitas to the Castro Valley.

For more information, and for additional links, see this episodes page at this podcasts forever home on CARouteByRoute.org.

This is Episode 4.02, which continues our exploration of Route 8, better known as Interstate 8. In this episode, we focus on the portion of I-8 from La Mesa (just outside of San Diego) to the Arizona border. We look at not only current I-8, but the routing of the predecessor route, US 80. We discuss the communities of La Mesa and El Cajon, Alpine and Descanso, Boulevard, the Mountain Springs Grade, Jacumba, Ocatillo (with a digression on the Imperial Highway), El Centro, Holtville and the Algondenes Dunes (with a digression on the Plank Road), Winterhaven and Yuma. We also briefly talk about the interesting routing of US 80 within Arizona, and how it differs from I-8. We talk about historical routings, projects along the route, and some significant names. In the next episode, we’ll turn our attention to Route 9, which currently runs from Santa Cruz to Los Gatos, but which once ran all the way to Castro Valley.

For more information and additional links, see the episode's page at the show's forever home on CARouteByRoute.org.

Welcome to Season 4 of CA Highways: Route by Route. Episode 4.01 is the first half of our exploration of Route 8. This episode covers the 8th State Highway, which became LRN 36 and later Route 194. It covers LRN 8, which ran from Ignacio (Novato) to Cordelia via Napa, and became parts of Route 37, Route 121, Route 12, and Route 29. We look at Sign Route 8, which became today's Route 26. And lastly, we look at I-8 in San Diego, including its historical ancestor US 80. This includes former Route 209 to Point Loma, which was part of LRN 12 and possibly US 80, and former Route 109, which became the portion of Route 8 W of I-5 (and you'll learn why that is not I-8). Episode 4.02 will pick up the story and explore the rest of I-8/US 80 between San Diego and the Arizona Border, including a discussion of the Imperial Highway.

For more information, including additional links, visit the Episode 4.01 page on CARouteByRoute.org

A New Year's Gift for you: Our last Bonus Episode of Season 3. Episode 3.15 features an interview with Claire Kennedy, Archivist for the Los Angeles Metropolitan Transportation Agency (LA Metro). In this role, Claire manages the LA Metro Archives, which date back to the 1800s and the earliest horse-drawn transportation in the city. These archives cover not only the wide variety of transit agencies in Los Angeles, but also the highway and road system as Metro is the Regional Transportation Agency. These archives are a public resource, and are open by appointment; information on how to make an appointment is in the podcast (and below). Note that we had some trouble with Zencastr this episode; we fell back to FreeConferenceCall.com. We'll pick up in the October with Season 4, which will cover Route 8 through Route 14.For more details and additional links, see the episode's page on CARouteByRoute.org

Bonus Episode 3.14 continues our inter-season gap between Seasons 3 and 4. This episode we're sharing an episode of the excellent Freeway Exit podcast from KPBS San Diego. Freeway Exit, hosted by Andrew Bowen, is an exploration of San Diego's freeways, their costs, and how they can be part of the solution. It covers the forgotten history of the urban freeway network, and how decades after that network was finished, some communities are still working to heal the wounds that freeways left behind. The episode we've chosen to share focuses on the Cabrillo Freeway, Route 163, through Balboa Park, and explores the question: Is it time to remove the freeway? After the episode, we have a discussion with Andrew about the podcast, the the San Diego freeway system, and how highways fit into the bigger picture. Oh, and we discover what he is doing next with the podcast, and try to convince him to do one on the Route 710 gap. This episode is also a test of using Zencaster to record the podcast. Hopefully it sounds better, and next time I'll move my microphone a bit further back. Zencaster also gives us the ability to have transcripts. Would folks want them included in the post? One more bonus episode is in the works: An interview with the LA Metro Archivist. We'll pick up in the October with Season 4, which will cover Route 8 through Route 14. PS: Support KPBS, or your local PBS/NPR StationFor more details and additional links, see the episode's page on the show's forever home: CARouteByRoute

Episode 3.13 is our first bonus episode, bridging the gap while we write Season 4. This bonus episode is a presentation that our co-host, Tom Fearer, gave at the Fresno Flats museum back in May 2025. The presentation focuses on the highways of the Oakhurst area, and was described as: "Since the establishment of the Stockton-Los Angeles Road in 1853 the Sierra Nevada foothills of what is now Madera County has been a hub of highway development. Much of the existing infrastructure in the area was established by the late 1880s with the plotting of the Fresno-Fresno Flats Road and Yosemite Stage Road. The area was of great interest during the early State Highway era due to the desirable access it could provide for logging interests and automotive based recreational travel to Yosemite National Park. Even Minaret Summit was briefly considered for a proposed extension of Interstate 70 into California before the era of environmental impact assessment began.” We'll pick up in the fall with Season 4, which will cover Route 8 through Route 14. I'm also looking into better software for recording the podcast: In particular, does anyone have opinions on Zencaster, Riverside, or Squadcast?

For more information, visit the episode's page at the show's forever home on CARoutebyRoute.org.