This is one of my all time favorite places, the intersection of two freeways over railroad tracks AND the Los Angeles River
Right next to the intersection of the I5 North and the 110 (first freeway ever built), there is a staircase to permit people to escape the higher freeway by foot, to the lower freeway and eventually to a street.
It's better seen than described but I would like to do a book about this place sometime.
Here is a view below, by streetlights at night:
View from above; this is a very complicated place.
View from atop the staircase: unfortunately lately most of the streetlights are burnt out so it's much darker now.
View looking down the stairs, if you looked left from the photo above, you would see this.
This is one of my all time favorite photographs, I love the geometries going on here.
View of the Spiral Staircase from the I5 onramp; the yellow barrels held sand for cars to hit; you can see this is not a very good place to linger.
Overall view in daylight.... I much prefer night.
The Spiral Staircase is far left of center near a leaning tree.
Above you can see how the two sides of the 110 freeway, north and south, cross the river.