At the first one, go left.
At the other one, go right.
I'm used to great sweeping limestone caves like Gaping Gill, so Los Angeles' sandstone cavern seemed very different to me.
It's dry and warm inside, although there are a lot of holes in the roof where it rains in when it does rain.
What makes it interesting is generations of people have carved the soft sandstone inside, and painted the walls outside. It's like an Angelino Lascaux or Tassili.
This was a fun trip, especially as I also got to eat a double-double at In 'n' Out Burger.