Firehole River starts as a backwoods stream and morphs into a river 21 miles long. The Firehold is a river that wanders through some of the most beautiful sights of Yellowstone National Park.

As it flows north, its first two significant sights are the Lone Star Geyser and the Kepler Cascades. The Cascades is a series of tiers that drop the Firehole River water over 100 feet into the Devil's Gorge.

The Cascades is just 2.7 miles south of the Old Faithful Area and a few steps from your car.

Kepler Cascades is one of the most accessible falls in Yellowstone to view. Excellent stop for those with mobility issues. The viewpoint is just feet from the parking area, and it is paved.

Firehole River cuts through the Old Faithful Area of the Upper Geyser Basin. It was a cold morning, and you can see the fog at the back of the picture. Old Faithful Geyser is about 50 feet to the left.

At the east end of the Kepler Cascades parking lot is the trailhead parking lot to Lone Star Geyser, a beautiful 4.8-mile roundtrip walk along the side of Firehole River on an old service road. I enjoyed watching a Common Merganser mother and her chicks swimming on the river during the summer of 2013. Lone Star erupts about every three hours.

Then, the river moves into the Upper Geyser Basin, the home of Old Faithful Geyser and Inn. The iconic 1904 Old Faithful Inn is probably within 150 yards of the Firehole River. The geyser is even closer.

Because the river moves through the geyser basins, its temperature can get up to 80°F (27°C) in the summer. The geysers and streams along its path drain tons of minerals into the water. Both are good reasons why you don't usually see many fish in the river as it goes through the Upper Geyser Basin.

In the picture on the right, you see Riverside Geyser erupting, and the spray and runoff end up in the Firehole River. Riverside Geyser's temperature is 201.2°F (94°C). And Riverside is only one of the geysers spilling hot water and minerals into the river.

Don't get fooled, the water for the geyser does not come from the river. That water is not hot enough to facilitate an eruption. Geysers setting next to a river or stream have their own "plumbing" system to deliver hot water to the geyser.

The beautiful Riverside Geyser erupting on the edge of Firehole River. I like to take pictures right across from the geyser in the bench area. Then, go to the bridge over the Firehole River and shoot some images with the river in the image. Riverside accommodates this plan by erupting for 20 minutes.

The Firehole River near Excelsior Geyser. Excelsior Geyser puts 4,000 gals of hot mineral-laced water a minute into the Firehole River.

The Firehole continues to flow north through and by the Midway Geyser Basin, as seen to the left. Did you catch that I said it flows north? Most of us are probably used to rivers flowing south, so why north in this case. It is simple. The Firehole starts just above the Continental Divide. This means water from the Firehole will eventually end up in the Pacific Ocean.

The Firehole River continues rambling along through the Lower Geyser Basin.

As it emerges from the basins, the water is tranquil, going for a distance until it starts to enter the Firehole Canyon. There are rapids at that point, and the water goes over the Cascades of the Firehole, where it drops 20 feet.

Just a short distance later the Firehole takes another drop at the Firehole Falls. Firehole Falls drops the Firehole River 40 feet as the river cuts through the Firehole Canyon. Rapid and noisy at the falls just a short distance upriver the water is tranquil and belies the rage that will soon take the river through the canyon.

The river eventually joins the Gibbon River to form the Madison River which flows out the west part of the park on its' way to the Pacific Ocean.

Below the Cascades of the Firehole is Firehole Falls.