Mud Volcano & Dragon's Mouth Spring (Yellowstone)

One of the areas along the Yellowstone roads contains two main attractions. It's in a fairly active area, as can be seen from the several areas of steam in this first photo.

First from the boardwalk you can see the Dragon's Mouth Spring, so-called because it belches large plumes of steam and roars like a dragon. It also sends out periodic waves of water.

The water drains out along a channel; the colors are from bacterial mats.

There is also a bubbling pool of mud.

And finally, the mud volcano is visible. It doesn't look impressive in this photo, but it's a boiling mass of muddy water that never stops exploding.