McDonald Observatory

The road to the summit of Mount Locke

Mount Locke is a high mountain peak at an elevation of 2.070m (6,790ft) above the sea level, located in Jeff Davis County, Texas, United States.

The summit hosts the McDonald Observatory, an astronomical observatory built in 1932. It’s one of the world's leading centers for astronomical research, teaching, and public education and outreach. The peak was named after G. S. Locke, an early rancher in the area.

How do I get to the McDonald's observatory?

The road to the summit is paved with steep grades. It’s called Texas State Highway Spur 78 or Spur 78. Starting from TX-118 road, the ascent is 2.73km (1.7 mile) long. Over this distance the elevation gain is 176 meters. The average gradient is 6.44%, with a maximum gradient of 11,4% At its terminus at the summit of Mt. Locke, Spur 78 has the distinction of having the highest elevation at any point on the state highway system.


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