The Boulder River Bridge

The pin-connected Pratt truss the panel names was the workhorse of Montana's first bridge era. From 1892 until 1915 counties bought such spans from private builders, many of them in Minnesota, because they were easy to assemble, inexpensive and reliable, the members joined by pins rather than rivets. In 1915 the Montana Highway Commission standardized a riveted design, and the pinned truss passed out of use. Gillette-Herzog left another in the state's record: Kalispell's Old Steel Bridge of 1894 over the Flathead, the first large steel bridge in northwestern Montana.

What the plaque says

The Boulder River Bridge The trusses on this structure were salvaged from the "Hubbard" or "Red" Bridge. The original structure was built by the Gillette- Herzog Manufacturing Company in 1899. The company was one of several Minnesota-based bridge construction firms active in Montana from the late 19th century to the early 1920's. The bridge was one of eight pin-connected Pratt through truss spans built by the company over a ten year period beginning in 1891. It provided access to Boulder from the rich mining and ranching operations located on the west side of the river. The design of this structure represents an accord between local citizens wanting to preserve some aspect of the original bridge, while providing a structure that could accommodate modern traffic needs. The new bridge represents the best of late 19th century and late 20th century technologies.

Where it stands

Worth the stop nearby

• Granite Mountain/Speculator Mine Memorial — 24 mi
  An overlook above the shaft where the 1917 fire began, and the letters some of the trapped men wrote while they waited.
• Mai Wah Museum — 25 mi
  Two brick buildings left from Butte's Chinatown, and a store whose goods came home after seventy years away.

More markers nearby

• Mining Country — 8.6 mi
• Jib Mill — 9.4 mi
• Elkhorn Mountain Volcanoes — 14 mi
• Freighters — 14 mi