YELLOWSTONE
Trailside Notes (Number One) 		NPS Logo

TRAILSIDE NOTES

III. Madison Junction to Old Faithful

Having visited the museum and enjoyed the view down the Madison Valley we set our mileage at zero, cross the concrete bridge and enter the Firehole River Gorge. We will drive slowly for the next two miles and observe the striking exposures of volcanic rock: Pinkish rhyolite, soft gray pumice, black, glassy obsidian, red and black perlite with glassy bubbles and breccia of cemented rock fragments, all interspersed with white, soft tuff. A magnificent wall of rock carved into pinnacles, rises before us. Alcoves in the wall result from the ease with which the perlite becomes weathered.

NOTE: The text is arranged in three columns. Objects on the tourists' right are described on the right-hand side of the page; those on the tourists' left, on the left-hand side. Objects in front and general descriptions occupy the middle of the page.

Due to changes in the road, distances as given are only approximately correct. Government markers by the roadside give more exact distances.

Web Edition Note: Due to numerous changes in the years since this guidebook was published, the text should solely be used for historical purposes.
MILEAGE
MILEAGE
0.3 How different is the grim mass of volcanic rock on the right from the exposure of rhyolite on the left! Can it be that we are looking at the face or side of what was once a glowing, viscous mass of molten rocks accompanied by intense heat and roaring with the crackling and crushing of its crust. It was a diabolical river of fire, slowly flowing from some unknown source. 0.3
0.5
We stop where a little stream trickles down over the rocks. Flowers abound. We dismount, identify the flowers, look up on the opposite side and discover an osprey's nest.
0.7
At the Rhinoceros Head we note that the volcanic mass has crossed the river to our side and as we look ahead we see that the road winds into it.

FIREHOLE CANYON FIELD EXHIBIT

The artificial cutting of the road gives us a rare opportunity actually to look into the very substance of a congealed flow of lava. The angular fragments show that there must have been volcanic explosions of great violence and of long duration. This was not a silent performance. It was no place for tourists.

Note the large boulders and angular fragments imbedded in the lava and volcanic ash. Those boulders of obsidian prove that there were old rhyolitic flows long before the expulsion of this mass of volcanic rubbish.
THE FIREHOLE FALLS1.0

The smooth surface of the rock at the left of and directly under the cascade is hard, horizontally-banded rhyolite. A huge mass of volcanic rubble seems to have flowed over this underlying rhyolite layer. The river finds it easy to cut through the coarse breccia but difficult to cut down through the hard rhyolite shelf. See how the softer breccia is undercut.

For the next half a mile the river passes through a narrow gorge with almost vertical walls. It is said to cut its gorge more rapidly than other rivers on account of the chemical content of the water coming down from the geyser basins.

1.5 As we proceed, note again how the river has undercut the cliffs and made a series of caves along a line horizontal with its present level. It must have been flowing at about where it is a long time but cavities above the stream prove that it once flowed at a higher level. How different is the craftsmanship of cold water flowing over the surface of igneous rocks from that of hot water flowing out from them. 1.5
1.9

A little fertile valley—grass bordered. This is evidence that for a time there was a dam holding the water back and thus producing a small lake or pond.

Lodgepole pines do not need very much soil. Note those growing on isolated boulders.

 1.9
THE FIREHOLE CASCADES2.3
Here the layers of lava stand almost on edge. The rhyolite and perlite, interspersed with slag, are full of spherules, indicating that, when hot, there were a multitude of gas bubbles. The river is having a hard time cutting through this dam of rock. As we proceed let us see if a meadow has not resulted—Yes, it has.
Look back. Observe Purple Mountain. We are nearing the top of these lava flows.
2.7

A fragment of rock by the roadside shows that when it was molten it contained bubbles of hot gas as large as eggs. Concretions have been formed within these cavities.

Lodgepole pines still persist in growing out of rocks.
3.2
The level verdure-lined stretches along its banks, the undercut rocks, its even gradient, and the peaceful flow of the river argue that its bed is composed of horizontal strata of uniform hardness. The green stretches are miniature terraces.
5.7

THE LOWER GEYSER BASIN

Having climbed the Firehole we are now again at about the same level as when we were at Swan Lake Flat and at the Gibbon Meadows.

 5.7
6.2NEZ PERCE CREEK

The trail at the left leads through Nez Perce Valley to Mary's Lake and from there to the Hayden Valley on the Yellowstone River above the Canyon. In this valley Chief Joseph, during his historic retreat, captured and subsequently released a party of visitors. This was in 1877, several years after the creation of the Park and before there was adequate supervision of the area.

The Lower Geyser Basin opens out before us. This is the largest geyser basin in the park. The Hayden Survey counted 680 geysers and hot springs in this basin.
7.9
Turn right at the "Paintpot" parking area and mount the hillock. Dismount and visit the extraordinary sights of thermal activity as indicated on several markers.

 Before seeing the sights, however, let us orient ourselves. Looking back we pick up our old landmark, Mount Holmes. The skyline at the left is the crest of Purple Mountain. To the west lie the small Twin Buttes. Observe the wide area covered by sinter. Consider the time necessary for its deposition. Think of the depth of the travertine at Mammoth. But this is not lime extracted from sedimentary rocks. It is silica extracted from volcanic rocks.
8.1
At the left a road branches to Firehole Lake, Steady and Great Fountain Geysers. Those taking this road will re-enter the main highway a mile to the south. There are several outstanding exhibits.

We enter a Lodgepole forest and continue south.
8.3
On the left, a quarter of a mile away, we see the cone of White Dome and the steam rising from Firehole Lake. We may wish that we had taken the branch road.
9.1
We meet the road which returns from Firehole Lake, etc.
9.6

LODGEPOLES

We continue to the south and presently come again to the Firehole River. Directly opposite is where Excelsior Geyser once threw up an amazing mass of water to a height of 300 feet, hurling rocks and sinter to a great distance. The story of Excelsior is one of historic interest.

 9.6

Parking area for Midway Geyser Basin. Dismount and read the story of Excelsior. Note the Grand Prismatic Spring.

Before leaving, glance up to the east and note that the old masses of lava are still with us. The scars on distant hills are evidence of its marvelous thickness.

The river is growing smaller.

 10.3
14
A little side road to the right leads to the Biscuit Basin.

UPPER GEYSER BASIN

The Ranger Naturalists at Old Faithful conduct parties to all places of interest in this the Upper Geyser Basin.

Sapphire Pool boils violently every fifteen minutes. Jewel plays at frequent intervals to a height of thirty feet. Silver Globe has a metallic luster, etc.

See the volcanic masses frowning down on us from the neighboring hills. There is evidently another plateau considerably higher than the one that we are on.

Large orange-colored patches mark the site of warm water seeping from the side of the volcanic hills.
14.4
Stop at Artemisia Geyser and examine also the vents on the opposite side of the road.
14.7
Morning Glory Pool and its highly colored corolla will give a thrill.
14.8

Cross the Bridge noting Riverside Geyser on the left. This geyser plays three times daily at regular intervals.

We are about to witness the most famous display of geyser activity in the world.

 14.8
14.9
Grotto Geyser has a fantastically shaped cone unlike any other in the park.
15
Giant Geyser, the broken cone on your left.
Inquire about it at the museum.
15.6 We pass Castle Geyser, with its characteristic cone, sweep in front of the famous Inn and come to rest at the parking space, adjoining the Old Faithful Trailside Museum. Here we find a bureau of information, an accommodating staff of ranger naturalists, and an outdoor auditorium where lectures appropriate to Yellowstone are given to the public without charge. 15.6

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Last Updated: 02-Apr-2007