Some of the geysers have build-up around their vents.
This one was Grotto Geyser
and this one Castle Geyser where a sign described that the buildup is so slow, maybe only a few inches in a 100 years so you can imagine how old this geyser must be.
Some of the more predictable or unpredictable depending on how you look at it had these signs.
I think you had better pack more than just a lunch for this one.
I was tired.
So I called it a day and headed back south out of the park to Grand Tetons National Park for camp figuring I can always come back to Yellowstone some other day on another trip by this area.
It is a big park and there is still more yet to see.
Back by Old Faithful they still hadn't got it working.