Cascade

During a geologically brief interval of only 3 million years, between 76 and 73 million years ago, volcanoes erupted blocks of congealed lava and volcanic ash interspersed with lava flows. The volcanoes that erupted this material have since been eroded. Mount Chisholm is a plug formed when magma intruded the surrounding volcanic rocks. Because the plug is a variety of basalt, an unusually hard rock, it eroded more slowly than the softer surrounding rocks. Narrow ridges exposed a mile northeast of this overlook are dikes that formed when magma filled north-south fractures in the fragmental volcanic rock. After cooling, the dikes formed hard rock that eroded more slowly than the surrounding volcanic rock to form narrow ridges.

Missouri River slowly eroded a valley through this volcanic field to form the landscape we see today. About 20,000 years ago the Continental Ice Sheet crept southward from Canada forming a dam against the north edge of the Highwood Mountains about 70 miles northeast of here impounding the Missouri River to fill Glacial Lake Great Falls. This ice-dammed lake flooded the Missouri River valley about 80 miles upstream from this overlook to the vicinity of Townsend, about 90 miles south of here. Around 15,000 years ago the Continental Ice Sheet melted enough to let the Missouri River flow in its former valley thus draining Glacial Lake Great Falls.

The Hardy Bridge

Great Falls contractors Angus McGuire and Evarts Blakeslee built the bridge spanning the Missouri River on the old highway below the overlook in 1931. Called Hardy Bridge because of the nearby community of that name, the bridge was an important part of U.S. Highway 91 until bypassed by the Interstate in 1968. The Hardy Bridge figured prominently in the 1987 film The Untouchables. Located at the fictional United States-Canadian border the bridge was the scene of a pitched battle between U.S. Treasury agents, the Canadian Mounties, and rumrunners employed by Chicago mobster Al Capone. During Prohibition in the 1920s, men regularly crossed into Montana from Canada, smuggling illegal whiskey and other spirits into the United States. This spectacular canyon and the old bridge were much more picturesque international border than the real thing 150 miles north of here.

Geo-facts:

• Named for a local settler, Mount Chisholm is the rocky promontory located directly west of this overlook.

• The Lewis and Clark Expedition traversed this canyon in July 1805. Meriwether Lewis noted the "steep cliffs" of the canyon here and mistakenly thought they were granite.

• Glacial Lake Great Falls at this overlook was over 450 feet deep.

Geo-activity:

• As you drive through this area, imagine what it looked like 75 million years ago when dinosaurs pulled the Earth and 20,000 years ago when it was part of Glacial Lake Great Falls.

Erected by Montana Department of Transportation.

The son of a wealthy St. Louis family, Charles M. “Charlie” Russell longed for western adventure. In 1880, at fifteen, he convinced his parents to let him visit Montana. He never looked back. For over ten years, he worked as a night herder during the summer and rode the grub line in the winter, all the while painting and sculpting western scenes. Russell met Ben Roberts in 1882. The two became friends, and after Roberts married Lela Gorham and moved to Lela’s hometown of Cascade, the cowboy artist often visited him in the off season. Roberts supported Russell’s artistic ambitions, and in 1890 he published Russell’s first book of illustrations. While visiting Cascade in October 1895, Russell met sixteen-year-old Nancy Cooper, who lived with, and worked for, the Roberts. Nancy and Charlie married a year later in the Roberts’ parlor. After the ceremony they moved into the small bunkhouse and studio behind the Roberts’ house where Russell always stayed when he visited the family. Russell spent $75 adding a lean-to kitchen and otherwise fixing up the place. “Our wedding trip,” Charlie remembered, “was a hundred yards to that one-room shack—and we walked.” Charlie’s marriage to Nancy marked a turning point in his career, and Nancy’s business acumen is often credited for his professional success. Her management started early, and within a year of their marriage the Russells had moved to Great Falls, where Nancy correctly felt there would be a larger market for Charlie’s work.

Erected by Montana Historical Society.

Lewis noted "an Indian road enters the mountain at the same place with the river... and continues along it's border under the steep cliff."

The Indian road Lewis mentioned follows the Hardy Creek drainage to the north. It was an important route for Indians seeking buffalo and other plains animals.

Roads like this were part of a network of trails that made up a transcontinental route called the Old North Trail which extended along the Rocky Mountains from Canada to Mexico, it is one of North America's oldest roadways and has been in use for over 12,000 years. It started as a footpath then evolved into a dog travois path, a horse travois path, wagon trail, and in some places gravel roads and paved highway. It was in continuous use until the automobile became common and the roads moved farther east on the flat country.

Erected by Portage Route Chapter, Lewis & Clark Trail Heritage Foundation (LCTHF).

"The Indians have informed us that we should shorty leave the buffaloe (sic) country after passing the falls" wrote Lewis. "this I much regret for I know when we leave the buffaloe that we shal (sic) sometimes be under the necessity of fasting occasionally."

The plains held an abundance of food from the vast herds of buffalo, deer and elk along with roots and berries from a variety of edible plants. They could not carry a large supply of this food with them so they had to depend on what could be found by hunters as they traveled. It was fine on the plains but once past the Tower and into the mountains it was just the opposite. The time in the Rockies was very basic subsistence. They ate what little came available with never enough to satisfy their their hunger.

Erected by Portage Route Chapter, Lewis & Clark Trail Heritage Foundation (LCTHF).

The entire expedition first camped in this area on their journey westward in July of 1805. Exactly a year later, Sergeant Ordway and a party of nine men retuned to this site.

Where were Captain Lewis and Captain Clark? Meriwether Lewis was following the Marias River and exploring with several of the men. Captain Clark had taken his party, including Sacajawea and her son, to follow the :Rochejone" (Yellowstone River). They were to all meet at the confluence of the Missouri and Yellowstone Rivers (near the present day border of North Dakota and Montana).

Sergeant Ordway and his party found the canoes that had been sunk in a pond near Beaverhead River the prior year. One canoe had been damaged and was cut up to reuse the wood as paddles. The party headed to White Bear Island south of Great Falls to dig up the items had been cached in this area and proceed onward.

This was the spot that the expedition visited exactly one year apart, once in July 17, 1805 and once again on July 17, 1806.

Erected by Lewis and Clark Trail Heritage Foundation.

On July 16, 1805 as the Expedition was about to enter the Rocky Mountains, Lewis describes some rapids "immediately at the foot of the mountain were the Missouri first enters." He also wrote about a "large pine tree situated on a small island at the head of these rapids." This is the first mention of Pine Island.

Later at winter camp on the Pacific Coast while compiling lists of rivers, creeks and significant geographical places, Clark includes Pine Island with mileage distances to other locations. Clark again uses Pine Island as a geographical reference point when describing Lewis' route over the Rocky Mountains and along the "Road to the buffalo" in July of 1806.

Erected by Portage Route Chapter - Lewis & Clark Trail Heritage Foundation (LCTHF).

Tower Rock marks he (sic) point where the Corps of Discovery left the plains and entered the Rocky Mountains The point where they left the familiar prairies and entered an new terrain.

Only July 16, 1805 Lewis recorded that "at this place there is a large rock 400 feet high which stands immediately in the gap which the missouri makes on a passage from the mountains: it is insulated from the neighboring mountains by a handsome little plain which surrounds its base on 3 sides and the Missouri washes its base on the other... this rock I call the tower. It may be ascended with some difficulty nearly to it's summit, and from it there is a pleasing view of the county we are now about to leave.:

Erected by Portage Route Chapter, Lewis and Clark Trail Heritage Foundation.

The Lewis and Clark Expedition passed through this canyon of "nearly perpendicular rocks" during its journey up the Missouri River in July 1805. Although the men grumbled about mosquitos and prickly pear cactus, the Corps of Discovery was clearly impressed by the Adel Mountain Volcanics, the eroded remains of a pile of volcanic rocks that flank the river for forty miles. The volcanic rocks you see next to the Interstate consist mostly of fragments from violent, explosive eruptions that occurred about 75 million years ago and continued for several million years.

Although the arrival of the Montana Central Railroad in 1887 did much to open this region to settlement, it was not until the early 1930s that a modern paved highway provided a direct connection between Helena and Great Falls through this area. U.S. Highway 91 wound its way along the Missouri River through the volcanic outcrops of the canyon, crossing the river over two large steel truss bridges that still carry traffic in the vicinity of Hardy and Wolf Creek. The Hardy Bridge is visible on the old highway below you. Though bypassed by Interstate 15 in the 1960s, today old U.S. 91 provides motorists a unique opportunity to experience a Great Depression era road through one of the most spectacular landscapes in Montana.

Erected by Montana Department of Transportation.

While walking the trail, look for the angular red, purple, gray, and green colored rocks. You are looking at geologic signs of transition between soft rock of the prairie and erosion-resistant igneous rock that make up the Adel Mountains. Volcanics. These rock fragments blasted skyward from violent volcanic activity some 68 to 75 million years ago. They settled and cemented together with volcanic ash. Over time the less erosion-resistant rock washed away reveling the formation you see today.

This area is a good example of a "habitat edge," where the prairies meet the mountains. Their rich diversity provides important places for wildlife to get water, nest, and seek prey. A botanical study of this area showed over 100 species of prairie and mountain plants found nowhere else but along mountain edges.

Erected by Portage Route Chapter, Lewis & Clark Trail Heritage Foundation (LCTHF).

In the area of present day Cascade, Montana Lewis and Clark had not seen any American Indians. In fact, they had not seen any Indians since entering Montana. However, there were signs of their presence in the form of "boothes" or leather lodges and very large pole lodges. Many historians believe that the Indians were watching the expedition without letting their presence be known. (Note the Corps of Discovery Expedition coming up the river in this painting by C.M. Russell.)

"Capt Lewis & 3 men went on to the mountain to take a meridian altitude, passed about 40 Small Camps, which appeared to be abandoned about 10 or 12 days. Suppose they were Snake Indians, a fiew miles above I Saw the poles Standing in thir position of a verry large lodge of 60 feet Diamater, & the appearance of a number of Leather Lodges about, this Sign was old & appeared to have been last fall" -- Captain William Clark, July 16, 1805

Erected by Lewis and Clark Trail Heritage Foundation.