In a city whose geography is often defined by freeways, seeing the Palisades Fire approach Interstate 405 on Saturday has alarmed many Angelenos.

The 405 freeway, as it’s known locally, has been a major north-south artery since the 1950s. Along with the 10, 5, 101 and 110 freeways, it is iconic — and both practical and symbolic of the city’s west side. It is also considered by some to be the busiest, most congested freeway in the country, travelled by hundreds of thousands of drivers daily. That’s because the 405 spawned development all along its path through LA County, from Encino at the southern edge of the San Fernando Valley south through the mountains to Brentwood, Santa Monica and Westwood. Residents rely on it as an exit route, connecting them to other freeways as well as to LAX and other local airports.

Now many of those areas are facing evacuation orders.

The Getty Museum, pictured in 2005, also came under threat from fire in 2017.Credit: DAVID MCNEW

On Saturday, when flames from the Palisades Fire appeared to spread east to Mandeville Canyon, locals knew that meant the blaze was creeping closer to the 405, near a busy mountain pass with spectacular views, including the hillside Getty Museum.

More than 2.8 million people live in the 20 cities lining the 405 as it passes through LA County, more than a quarter of the population of the country’s largest county.

Many remember apocalyptic images of a firestorm descending on that area captured during the Getty Fire in 2019 and Skirball Fire in 2017, which prompted evacuations and destroyed homes. The freeway, and the Getty, emerged unscathed.

But the Palisades Fire has already grown larger and far more destructive. The cities now in its path are larger and more densely packed with homes and businesses — and closer to the centre of sprawling Los Angeles.

Washington Post