Mt. Hamilton Road (part of State Route 130) is a sinuous 19-mile (31 km) road located in California's Diablo Range, in Santa Clara County, California, climbing up to Mount Hamilton, a mountain pass at an elevation of t 4,216 feet (1,285 m) above the sea level, and the site of Lick Observatory, the first permanently occupied mountain-top observatory. The road is advertised to include 365 curves, one for each day of the year.
The drive is definitely worth it. There are spectacular views of San Jose and the rest of the Santa ClaraValley below. Built in 1875–76 in anticipation of the observatory, and the need to carry materials and equipment up the mountain in horse-drawn wagons, the grade seldom exceeds 6.5 percent. The road follows a gradual grade laid out over a century ago for horses and carts. It has many sharp curves and is quite narrow in places. There are no gasoline or food services at Mt. Hamilton or anywhere along the road outside of San Jose.
The surface of the road is asphalt, and chains or snow tyres can be required throughout the year. At 4,209 feet, weather on Mt. Hamilton may be cool and changable, so bring a sweater or coat and remember that it becomes cooler and often more prone to storms at higher elevations.