No, not that Grand Canyon. The one around here.
What few know is there's a Grand Canyon in the mountains north of Pasadena, California. That's because there's no trail there and you need to occasionally slide on your rear due to steep dirt slopes. I also made it extra interesting by, despite pangs of thalassophobia, going through a bit of a pool.
Based on the satellite photos which have red fire retardant but which don't show much burning, I assume the Canyon escaped the otherwise devastating Eaton Fire relatively unscathed. But, because that part of the forest is closed I can't check it out.
When it does open again, you can follow the directions here. You walk up the Mt. Lowe Road and then, at the Mt. Lowe Trail Camp you put into the canyon.
Just before we put in, the Voice of Doom emanated from a hammock at the Camp. Said Voice of Doom warned us how tough it would be but we pushed ahead. There are rough use trails in places but usually you're making your own trail. The slopes are indeed steep and loose, and currently covered in leaves. There's lots of living and dead plants to work your way through and slippery moss-covered rocks.
Partway through you run across an abandoned, roofless cabin. There are also bits of metal; at least one piece looked like it could be from the plane crash mentioned at the link. Around the cabin the travel is a bit easier, but don't get your hopes up: there's plenty of bushwhacking before you finally join the maintained trail in Millard Canyon. The Dawn Mine is shortly after that. You follow the regular trail down and eventually it loops back to the starting point.
