Island Circumference Route

The Island Circumference Route encircles the entire perimeter of Wild Horse Island, the largest island in Flathead Lake and one of the most wildlife-rich state parks in Montana. Accessible only by private boat or water taxi from the Big Arm unit, the island exists in remarkable ecological isolation that has preserved populations of wild horses, bighorn sheep, mule deer, and bald eagles that roam freely without the disturbance of roads or permanent human habitation.

The circumference route follows the rocky shoreline and rises over interior ridgelines, delivering continuous panoramic views of Flathead Lake in every direction. The lake itself is the largest freshwater lake west of the Mississippi River, and its sheer size creates an almost ocean-like sense of scale when viewed from island high points. Bighorn sheep are commonly encountered in the rocky terrain along the western shore, often showing remarkable tolerance for patient and respectful observers. Wild horses graze in the open grassland meadows of the island interior, descendants of horses that have lived here for generations. Bald eagle nests occupy several large ponderosa pines in the northern portion of the island, and the adult eagles are conspicuous throughout the breeding season. The full circumference is a full-day undertaking requiring early arrival by boat and careful attention to return water taxi schedules.