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Tens of millions of years ago, the San Juan River in what is now southern Utah shared some characteristics with today’s Mississippi River. In a bygone geologic era, the San Juan flowed across a relatively flat plain that formed in an ancient marine environment. Unencumbered by rugged terrain, the river was free to take a long, meandering path on its gradual journey downslope.
But this part of the San Juan changed when geologic forces pushed the Colorado Plateau upward. Some experts think that within the later stages of this “still-enigmatic” history, starting around 20 million years ago, the plateau’s rise elevated the San Juan’s headwaters, which increased the river’s gradient and sped its flow. With that, the water’s erosive power intensified, and the river started carving its winding path deeper and deeper through 300-million-year-old rock.
Today, on its westward path to Lake Powell, the San Juan River flows through an impressive series of entrenched meanders, also known as “goosenecks.” An astronaut aboard the International Space Station photographed the stark desert topography on October 6, 2026.
In Utah’s Goosenecks State Park, the river runs through a canyon 1,000 feet (300 meters) deep. In places, it nearly loops back on itself, making horseshoe-shaped bends. One section is so curvy that the river travels 5.5 miles (8.9 kilometers) between two points that are only 1.3 miles (2.1 kilometers) apart as the crow—nay, goose—flies.
While the goosenecks are an unusual geologic wonder to behold by day, the area’s dark skies are a spectacle by night. Goosenecks State Park’s remote, high-desert location and 360-degree views of the sky helped earn it an International Dark Sky Park designation in 2021. According to DarkSky International, features such as the Double Cluster in Perseus and the Messier 24 star cloud in the Sagittarius spiral arm of the Milky Way are visible to the unaided eye from the park. In November 2026, dark skies offer the chance to view several meteor showers, with the Northern Taurids, Southern Taurids, and Leonids reaching their peaks throughout the month.
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Last checked 6 Nov 2026, 6:47 pm IST · Coverage & methodology
