One of Colorado’s great wildlife spectacles is underway.

And for a 42nd year, the Monte Vista Crane Festival returns to honor it.

The festival runs March 7-9 — three days of arts, exhibits, lectures and tours to the surrounding, nutrient-rich fields where thousands of greater sandhill cranes are “spring breaking” as part of their annual migration.

The majestic birds stop in the also-majestic, mountain-rimmed San Luis Valley for much of February and March. And people flock with them, cameras and binoculars in tow.

Bring along these fun facts as well:

1. Their path is long.

The cranes come to the San Luis Valley from wintering nests in the southwest U.S. and northern Mexico. They feast on the valley’s plentiful grains left on harvested barley fields and bugs around widespread wetlands before continuing on to summer breeding grounds in the northern Rockies and plains.

2. They are known to be ancient.

Their mesmerizing, chortling calls ring through thousands of years of history — “perhaps millions of years prior to the first appearance of humans,” according to the Colorado Crane Conservation Coalition. Humans left a mark high on a cliff at the edge of the valley. Monte Vista Crane Festival calls it “a well-protected, 6-foot-long petroglyph that is unmistakably a sandhill crane. So, as much as 2,000 years ago, humans were celebrating the return of these magnificent birds to the Valley of the Cranes.”

3. They are magnificent indeed.

The gray-bodied, long-legged greater sandhill cranes commonly stand 4 feet tall and spread their wings 6 feet long. Their heads are capped with red, a striking spot seen from afar as they take flight, backdropped by the Sangre de Cristo Mountains. It is said they can fly more than 200 miles a day. And yet they thrive on the ground, making their nests there rather than in trees. Colorado Crane Conservation Coalition notes their feet “with three primary toes” that “are extremely powerful and tipped with impressively sharp claws.”

4. They mate for life.

Knowing this makes their courtship dances all the more poignant to watch. It’s what human admirers come to see: the cranes leaping up and down, spreading their wings, bobbing their heads and singing their songs. They typically mate by the age of 5 and return to the same nest sites every spring. Some pairs occupy the same nesting site the entirety their 20-plus years of life.

5. They visit elsewhere in Colorado.

The birds stopping in the San Luis Valley are part of the Rocky Mountain population of greater sandhill cranes. While more abundant in this part of southern Colorado, they are also known to nest in northwest parts of the state. Smaller numbers have been seen in far western Mesa, Montrose and Delta counties as well.