Category: Interstate

CA RxR 5.01: I-15 (Part 1): South of TemeculaCA RxR 5.01: I-15 (Part 1): South of Temecula

September 18, 2026September 18, 2026| DanielDaniel| 0 Comment| 6:21 am

Welcome to Season 5. We start the season with three episodes covering Route 15. The first (this episode), covers LRN 15, Sign Route 15, and today’s Route 15 between San Diego and Temecula. LRN 15 ran from what is now Route 1 near Fort Bragg to what is today’s I-80 near Emigrant Gap; it is today’s Route 20. Sign Route 15 is what became Route 7 and later I-710, and is today’s Long Beach Freeway. We have some interesting exploration of the ends of Sign Route 15 in Pasadena and Long Beach. We then turn to the main focus of the episode: Route 15, which runs from San Diego to the Nevada border, and has a complicated history. So complicated, in fact, that this episode focuses only on the portion between San Diego and Temecula, exploring both former Route 103 and US 395, as well as the transition from US 395 to today’s I-15 routing. Episode 5.02 will cover Temecula to Devore, and explore the history of I-15, I-15E, I-215, Route 71, US 91, US 395, and Route 194. Lastly, Episode 5.03 will cover Devore to Nevada, including I-15, US 395, US 66, US 91, and US 466 (with a bit of Route 195 and US 95 thrown in).

Here’s the link to the show:

And here’s the link on Spotify for Creators:

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CA RxR 4.07: Route 11: From Pasadena to the BorderCA RxR 4.07: Route 11: From Pasadena to the Border

February 21, 2026February 21, 2026| DanielDaniel| 0 Comment| 8:01 am

In Episode 4.07, we examine Route 11.  We’ll start by exploring LRN 11, which was essentially the first state highway, running from Sacramento to Placerville, later extended to run from Antioch to the Nevada State Line near Lake Tahoe. Today, it is primarily US 50 with a bit of Route 160. We then the original Sign Route 11, which was LRN 165 and LRN 205, and is today’s Route 110. It was also US 60, and is perhaps better known as the Harbor Freeway and the Pasadena Freeway / Arroyo Seco Parkway. We explore the history and various routings of Sign Route 11, including the history of the Figueroa Tunnels. Lastly, we explore the current Route 11, which is a short route near the Mexico border that connects the San Diego Freeway System (Route 905/Route 125) to the Otay Mesa East port of entry.

On deck: In episode 4.08, we start a three-episode group that will cover Route 12. Route 12 runs from Route 1 near Valley Ford to US 101 and thence to Sonoma area. It then runs through Napa to meet I-80 near Cordelia. That part is episode 4.08. Episode 4.09 will cover Route 12 from I-80 near Suisan City through the Sacramento Wetlands to Lodi and Route 99. Lastly, Episode 4.10 will cover Route 12 from Route 99 to the Sierra Foothill and San Andreas, where it meets Route 49.

Here’s the link to the show:

And here’s the link on Spotify for Creators:

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CA RxR 4.06: I-10: San Bernardino FreewayCA RxR 4.06: I-10: San Bernardino Freeway

January 29, 2026January 29, 2026| DanielDaniel| 0 Comment| 6:10 am

Episode 4.06 continues our exploration of Route 10.  Episode 4.05 covered the first segment of Route 10: The Santa Monica Freeway between Route 1 and the I-5/US 101 junction. This episode, 4.06, covers the second segment of Route 10, from US 101 to the Arizona Border. Along the way, we explore the former I-110 segment, Route 10S, and do a deep dive into the US highways that shaped this segment of I-10: US 60, US 70, and US 99. We explore the historical routing of those highways across this segment. We also look at some of the names on the highway, and current projects along the highway.

In the next episode, 4.07, we’ll turn our attention to Route 11. We’ll start by exploring LRN 11, and then look at the original Sign Route 11. This was originally tied closely with the development of US 66, and became today’s Route 110. We’ll also talk about the current Route 11.

Here’s the link to the show:

And here’s the link on Spotify for Creators:

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CA RxR 4.05: I-10: Santa Monica FreewayCA RxR 4.05: I-10: Santa Monica Freeway

January 7, 2026January 7, 2026| DanielDaniel| 0 Comment| 6:04 am

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.

Here’s the link to the show:

And here’s the link on Spotify for Creators:

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CA RxR 4.02: I-8 and US 80 Between El Cajon and the Arizona BorderCA RxR 4.02: I-8 and US 80 Between El Cajon and the Arizona Border

November 7, 2025November 7, 2025| DanielDaniel| 0 Comment| 11:35 am

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.

Here’s the link to the show:

And here’s the link on Spotify for Creators:

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CA RxR 4.01: I-8, Former Route 109, Route 209, and US 80 in San DiegoCA RxR 4.01: I-8, Former Route 109, Route 209, and US 80 in San Diego

October 17, 2025October 17, 2025| DanielDaniel| 0 Comment| 6:46 am

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.

Here’s the link to the show:

And here’s the link on Spotify for Creators:

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CA RxR 3.12: Route 7: From Long Beach to the BorderCA RxR 3.12: Route 7: From Long Beach to the Border

June 22, 2025June 22, 2025| DanielDaniel| 0 Comment| 1:18 pm

Episode 3.12 brings Season 3 to a close, modulo our bonus episodes. In Episode 3.12, we explore all things Route 7. As is our tradition, we start by looking into the 7th state highway, the Kings River Canyon Road, and LRN 7, which included portions of US 40 and US 99W. We then turn our attention to various incarnations of Route 7: Sign Route 7, both the section along the Eastern Sierras that is now US 395 and US 6 and the section that became Sepulveda Blvd in Los Angeles; 1964-1981 Route 7, which was the Long Beach Freeway before it was renumbered into I-710; and the current Route 7, which is a small border connection route near a new entry point near Calexico. We’ll then be taking a short break, during which there will be some bonus episodes. We’ll pick up in the fall with Season 4, which will cover Route 8 through Route 14. I’m also going to be working on improving the sound quality of the podcast once I retire in July.

Here’s the link to the show:

And here’s the link on Spotify for Creators:


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CA RxR 3.10: I-5: Gateway to OregonCA RxR 3.10: I-5: Gateway to Oregon

April 28, 2025April 28, 2025| DanielDaniel| 0 Comment| 5:09 pm

Episode 3.10 completes our exploration of I-5, looking at the segment that was former US 99, LRN 3, between Red Bluff and the Oregon Border. Along the way, we visit Red Bluff, Anderson and Redding, the Lake Shasta Area, Dunsmuir, Mt. Shasta, Weed, Yreka, and run into a California Agricultural Inspector who was trapped in a bottle by a witch. Our next episode will move us to the next highway, looking at US 6 and all things Route 6 in California.

Here’s the link to the show:

And here’s the link on Spotify for Creators:


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CA RxR 3.09: I-5: Former US 99WCA RxR 3.09: I-5: Former US 99W

April 6, 2025April 6, 2025| DanielDaniel| 0 Comment| 12:25 pm

Episode 3.09 continues our exploration of I-5 with the segment from Sacramento to Red Bluff, which primarily incorporates the former LRN 7 / US 99W routing between Woodland and Red Bluff, and a new routing that roughly followed LRN 238, then LRN 50 and LRN 232 between Sacramento and Woodland (near former Sign Route 16 and Sign Route 24). We talk about this history of this segment, as well as some discussion of historical routings in Natomas, Woodland, Williams, Willows, Corning, and Red Bluff. Our exploration of I-5 finishes in Episode 3.10, where we explore the former LRN 3/US 99 segment between Red Bluff and the Oregon Border.

Here’s the link to the show:

And here’s the link on Spotify for Creators:


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CA RxR 3.08: I-5: Whatever Happened to I-5WCA RxR 3.08: I-5: Whatever Happened to I-5W

March 13, 2025March 13, 2025| DanielDaniel| 0 Comment| 2:49 pm

Episode 3.08 continues our exploration of I-5 with a slight digression: A discussion about I-5W. In the late 1950s, I-5W was proposed as a spur route from I-5 running along what is today Route 132, I-580 (both the Tracy Diagonal and the former US 50 portion between the I-205/I-580 junction and Oakland/Berkeley), I-80 between Berkeley and near Vacaville, and I-505 between Vacaville and I-5. This short episode explores these pieces and their history. In Episode 3.09, we return to I-5 proper when we explore the former US 99W section of I-5 between Woodland and Red Bluff.

Here’s the link to the show:

And here’s the link on Spotify for Creators:

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