People often ask me what my favorite national park is, and I always answer Yellowstone. Why? Because it's so rich. You've got incredible wildlife, great mountains, lakes and streams, and, of course, the geothermal resources.

While most geothermal attention seems to go to Old Faithful, there are countless geysers that will impress you with their displays. Jeremy Sullivan nailed this shot of Great Fountain Geyser along Firehole Lake Drive. The backlighting really lends texture and even a little personality to Great Fountain.