Inside Jack Jones Ice Cave near Tennant, California.  There is a north & south passage, this is at the very end of the south passage.  The initial entrance had plenty of ice stalagmites but after crawling through some intense breakdown the last 300 feet of this portion opened into a magnificent tunnel w/ virtually no breakdown, high ceilings up to 30 feet up & ending abruptly here at this lava seal.  The walls are adorned with many signatures, most of them well over a century old.  Common years of visitation include 1908, 1920, 1992, & 1995.  One panel of the wall appears to perhaps have signatures in the 1890s.