The construction for the Milk River Centennial Cairn began early in 1966 with the collection of suitable rocks locally. The rocks which were eventually included in the cairn come, appropriately enough, from all over North America, but the majority of them were collected in this vicinity. Although the base rocks of the region are primarily limestone and sandstone, igneous outcrops are found in the vicinity of the Sweetgrass Hills, and large areas of glacial deposition occur; thus a wide variety of rocks may be gathered within a few miles, including agate, petrified wood and dinosaur fossils. Examples of this are built into the cairn.
Actual construction of the cairn began in June 1966, and the task was completed just prior to the Sunshine Centennial Celebrations on the first of May, 1967. Although many people contributed to its building, special mention must be made of John Kolesar and Alva Bair, both of Milk River, and Lawrence Halmrast of Warner. Without the skill and technical knowledge of these men, the project would not have been possible.
The completed cairn weighs a total of 37 tons, including the pediment, is 12 feet long, 61/2 feet high and 31/2 feet thick. It carries a large bronze plaque outlining the history of the eight flags and stands in front of eight flag poles bearing the flags themselves.
In 2012, Milk River Centennial Cairn became one of the amazing Alberta icons featured in the “Passport to Alberta’s Community Icons“. The passport project gives an opportunity for visitors to go to each community to see the unique and interesting icons and get their passport stamped at the locations noted in the passport. Then the visitors mail in their passport for a chance to win prizes. To get your passport or to have it stamped visit the Town Hall on 240 Main Street or the Travel Information Centre just south of town on Highway 4.