We decided to head to the north end of the park today and found quite a bit of thermal activity. We thought that most of the thermal activity was in the south around Old Faithful. The south end has most of the larger geysers. We found a few geysers in the north. When they erupt they only shoot up several feet as opposed to those in the south which go several hundred feet into the air.
In the picture of park headquarters the red roofed buildings on the right are the original headquarters buildings which are still in use. (Click on picture for larger view, then you can click on any portion of the larger view to zoom in).