Before Lewis and Clark reached the Gates of the Mountains on their westward journey to the Pacific Ocean, they passed the Great Falls of the Missouri, near present-day Great Falls. On June 13, 1805 Lewis and a small party ahead of the other expedition members reached the Great Falls. He discovered that, rather than one waterfall as he expected, based on information received from the Mandan Indian villages, there was a series of five cascades that the expedition would need to portage around. When Captain Clark arrived on June 16 with boats, they discovered that the best portage route around the falls was on the south side of the river and was 18 miles in length. To haul their heavy dugout canoes and baggage around the falls they constructed two wagons, which were strapped to the men and pulled. The pirogue was too large to portage and was cached at the falls with other excess baggage. In all, the portage required four round trips and two weeks to complete. Though the portage was anticipated to take much less time, the delay gave expedition members time to hunt and fish and build up a large store of dried fish, meat, and pemmican. They had been warned at the Mandan villages that game would be scarce once they reached the Rocky Mountains.

Lewis and Clark left the Great Falls heading upriver along the Missouri on July 15, 1805. To lighten the laden canoes, the two captains, along with two privates, walked along the river's shore. On July 16, as they proceeded south on the river, they observed willow shelters accompanies by ten-day-old horse tracks. They guessed that these remains were left by the Shoshone whom they were anxious to find and bargain with for horses. Lewis, his servant York, and two privates set out ahead of the party in search of the Shoshone but were unable to locate them. Convinced the Indians were avoiding the party because of the amount of shooting the hunters were doing, on July 18, near present-day Holter Dam, Captain Clark set out ahead of the expedition on shore, with York, J. Fields, and Potts, in hopes of making friendly contact with the Indians. As they traveled overland on that day, they observed a large Indian lodge about 60 feet in diameter constructed the previous fall. Approximately "80 leather lodges" were located in the nearby vicinity constructed at the same approximate date.

During this time, Lewis and the other expedition members continued upriver toward the Gates of the Mountains, using towlines and poles to ascend the ever-more-challenging Missouri. As they ascended the river, the explorers observed great quantities of currants on either side. Lewis commented on the number of sunflowers blooming along the river bottom, noting that the Indians of the Missouri made great use of the sunflower seed, grinding it to make bread or for thickening soups. On July 18, Lewis and his men camped along the Missouri on its north side about 17 river-miles north of the Gates of the Mountains, finding the territory extremely rugged with many wide and winding bends. On July 19, as they ascended the Missouri, Lewis stated that they were "almost suffocated in this confined valley with heat." He further described the area in his journal that day:

This evening we entered the most remarkable cliffs that we have yet seen; these cliffs rise from the waters edge on either side perpendicularly to the height of 1200 feet. Every object here wears a dark and gloomy aspect. The tow[er]ing and projecting rocks in many places seem ready to tumble on us. The river appears to have forced its way through this immence body of solid rock for the distance of 5 ¾ Miles and where it makes it's exit below has th[r]own on either side vast columns of rocks mountains high...

. . . the river appears to have woarn a passage just the width of its channel or 150 yards. It is deep from side to side nor is there in the 1st 3 Miles of this distance a spot except one of a few yards in extent on which a man could rest the soal of his foot. Several fine springs burst out at the waters edge from the interstices of the rocks. It happens fortunately that altho' the current is strong it is not so much so but what it may be overcome with the oars for there is hear no possibility of using either the cord or Setting pole. It was late in the evening before I entered this place and was obliged to continue my rout until sometime after dark before I found a place sufficiently large to encamp my small party; at length such a one occurred on the lard. Side were we found plenty of lightwood and pic[t]ch pine. This rock is a black granite below and appears to be of a much lighter colour above and from the fragments I take it to be flint of a yellowish brown and light creem-coloured yellow. From the singular appearance of this place I called it the gates of the rocky mountains.

Lewis also noted on this day that they had observed no buffalo since entering the Big Belt Mountains.

On the night of July 19, there is some question as to where Lewis's party camped witching the Gates of the Mountains. A bronze plague at Meriwether campground, placed there by the Daughters of the American Revolution, identifies this spot as the July 19th camp. However, Lewis's journals for the following day state that they only traveled .5 miles up the river before coming out of the river canyon. Further, they reach this open place at 6 in the morning, which hardly seems possible had they set out from Meriwether campground that morning paddling upriver. Robert Bergantino, an amateur historian who has painstakingly mapped the routes of Lewis and Clark, feels strongly that the camp was on the southeast side of the river on a small level area big enough to accommodate Lewis and his fifteen men. The location of the July 19, 1805, campsite may also be in Field's Gulch. Because the explorers only camped in the Gates of the Mountains one night, they left behind little or no remains that would help document the exact location of their camp. Their campsite may also have been inundated by the construction of Hauser and Holter Dams. As a result, the location of the camp remains a mystery.

The passage of this section of the river must have been somewhat disconcerting for the explorers. Though the previous landmark of the Great Falls was a welcome sight, the effort the portage required was far beyond what they had expected. Then to proceed through the cataracts of the Gates of the Mountains must have left Lewis anticipating even further delays before reaching the headwaters of the Missouri. Express his fears, Lewis stated that surely the river could not have "woarn a passage" through every "immence body of solid rock" such as it had through the Gates of the Mountains.

Historic Background

The history of the Gates of the Mountains area centers on mining, river transportation, homesteading, and early recreation. Though mining occurred in the Gates, it was not at the level of intensity witnessed in many areas elsewhere in the Big Belt Mountains. Evidence of mining activity is present at the mouth of the Gates, in the American Bar area where hydraulic mining and dredging for both gold and sapphires occurred. The 1873 GLO plat map shows three different roads leading to American Bar from the east. On the west side of the river, a road that proceeds toward Helena is labeled "Road to American Bar." A structure appearing on the map on American Bar is labeled "Peck," indicating that it was occupied by this family or individual. The 1873 map also shows a structure located across from American Bar on the west side of the Missouri River on what later became the Hilger homestead. The structure was occupied by the Ming family and is listed on the map as "Ming." The 1915 GLO map shows a blacksmith shop, bunkhouse, barn, and residence on American Bar. The 1919 GLO map lists these buildings as being part of Homestead Entry Survey No. 379. This homestead is listed under the name Joseph Hoffman. Much of the American Bar area is in private ownership and, unfortunately, was not included as part of the heritage survey area.

At the north end of the Gates of the Mountains, mining also occurred on Ming Bar. The 1902 GLO plat map shows two mining claims on this bar. Land status maps, dated 1949, indicate an aviation landing strip was present on Ming Bar.

The Hilger family, who homesteaded the area at the southern mouth of the Gates of the Mountains on the west side of the Missouri River, figure prominently in the area's history. Nicolas Hilger II came to Helena during the gold rush of 1864. He returned to his home of Minnesota in 1866, to bring his family back to Montana in a covered wagon. A year later, Nicolas and his family purchased the Hilger homestead from the Ming family. That same year, Nicolas became a Helena judge and was thereafter referred to as "Judge Hilger." Judge Hilger had four sons and four daughters. His son, Nicolas D. Hilger III, was born in 1874 and was called N.D.

In 1872, Thomas Roberts was commissioned to examine the Missouri River between Great Falls and Three Forks to determine which section were navigable. Roberts concluded that 102 miles of the river between Prickly Pear Creek and the Great Falls were navigable. But it wasn't until 1886 that steam navigation became a reality on the Upper Missouri when Judge Hilger purchased a 55-foot-long stern-wheeler. He named the boat the Rose of Helena and used it to take tourists through the Gates of the Mountains. The boat eventually was used to travel to the Great Falls, with the trip's duration consuming two full days.

In 1908, Hauser Dam broke and flooded the area downstream sweeping the Hilger house up in the floodwater. The house is reported to have floated around the lake in a circular pattern, settling again almost exactly in its original spot of 1864. The house required only minor repairs, and the family continued to live in it for many years after. In 1913, Judge Hilger died and left the Hilger ranch to his son N.D. The stone house that now sits on the Hilger Ranch was built by N.D. in 1918 of stones gathered from the family property. The Hilger Ranch was lost through bankruptcy in 1920, but N.D. continued to live on a small piece of land along the Missouri and assisted his brothers in running the tour boats up and down the canyon. In 1922, another of Judge Hilger's sons, David, formed the Gates of the Mountains Transportation Company and started operating the tour boats on a regular basis. The four children of N.D. (Dan, Susan, Bryan, and Babe) bought the Hilger Ranch back in 1933. Two years later, they bought their first Hereford and began breeding cows. In 1973, Judge Johnson of Butte purchased the Gates of the Mountains Transportation Company from David Hilger's family and formed the Gates of the Mountains Foundation, which continues to offer tour boat trips in the Gates. The Hilger Ranch was sold to a neighboring ranch owner in 1983 and then to Cathy Campbell, the current owner, in 1986.

Hydroelectric development is also a significant component of the history of the Gates of the Mountains. Holter Dam, located approximately 7 miles north of the northern mouth of the Gates of the Mountains, was constructed beginning in 1910. The construction of this dam inundated lands witching the Gates of the Mountains canyon. Historic photographs of the Gates, reflect how much lower river levels were prior to dam inundation. River levels were approximately 14 feet lower in historic times than they are today.

Construction of the Holter Dam was carried out over an eight-year period. The camp associated with the dam construction was extensive and included a photographic studio, school, blacksmith shop, boarding house, store, barber shop, gardens, hospital, bunkhouses, and single family residences. The number of workers housed at the camp varied between 400 and 725 and included engineers, skilled mechanics, artisans, and common laborers. The area that housed the Montana Power Company employees was separate from the foreign laborers camp with the MPC camp being very elaborate. Heritage survey work conducted t the Holter Dam construction camp indicates that the remains of over fifteen original structures still exist. The Man Gulch fire in the Gates of the Mountains in 1949 was an extremely important historical event. Thirteen men died in this fire on August 5, 1949. The event changed the way fires were fought in the Northwest as the concept of setting backfires gained acceptance after this fires were fought in the Northwest as the concept of setting backfires gained acceptance after this fire. More emphasis was placed on smokejumper and firefighter training after the Mann Gulch tragedy. The site where thirteen men died, located a few miles up Mann Gulch, is listed on the National Register of Historic Places. A sign commemorating the event lies at the mouth of Mann Gulch along the Missouri River. The Gates of the Mountains area is currently managed as a recreation corridor. The Montana Department of Natural Resources and Conservation, the USDA-Helena National Forest, and the USDI-Bureau of Land Management, manage the area collectively. As part of management of this area, these three agencies interface with Pacific Power & Light-Montana (PPLM), formerly the Montana Power Company (MPC), regarding the management of resources within the corridor. Because the river corridor is a reservoir created by the construction of Holter Dam, PPLM, as required by its permit with the Federal Energy Regulatory Commission (FERC), is responsible for damage to resources located within the high water level of the river. The FERC license for seven hydroelectric facilities, including Holter and Hauser Dam, was issued in 1956. Intensive heritage survey and test excavation work conducted in the 1990s was accomplished as a requirement for the recent re-licensing of these facilities.