Hear Bull Elk Bugle in Yellowstone
Each fall, Yellowstone's valleys fill with one of the wildest sounds in North America: the bugle of a bull elk. Part whistle, part roar, ending in a series of grunts, it carries for a mile across the mist. The rut peaks in September, and the surest place to hear it is around Mammoth Hot Springs, where big bulls gather harems on the open lawns, or along the Madison River at dawn.

This is not a sight you tick off, it is a sound that finds you. The bugle is a bull advertising his strength to rivals and to cows, and for a few weeks the whole valley becomes his stage. September is the peak, with dawn and dusk the best hours, and Yellowstone's herds make it one of the most reliable places on earth to witness the rut. Keep your distance: a bugling bull is magnificent and unpredictable.