Trinidad Head Light, Coastal lighthouse in Humboldt County, California, US

Trinidad Head Light is a low, square brick tower painted white, built in 1871 on a headland about 20 miles north of Eureka, California. The lantern sits only 20 feet (6.1 m) above the ground, but the bluff gives the light a focal height of 196 feet (60 m) above the sea. It shows a white flash every 4 seconds with a nominal range of 14 nautical miles.

The tower was built in 1871 and marked an important point in shipping history along the Northern California coast. Throughout the 20th century, the light was automated and remains in operation today.

The original 1871 tower and the 1900 fog-signal building are contributing elements of the Trinidad Head Light Station, listed on the National Register of Historic Places on September 3, 1991. The 1969 keeper's building is non-contributing. In 1949 the Trinidad Civic Club built a replica tower in a harbor park and installed the original lens there as a memorial to those lost or buried at sea; the 4,000-pound bell stands beside it.

The grounds are accessible via marked trails that start from the visitor area, offering a comfortable walk across the headland with ocean views along the way. The best views come on clear days when visibility is good.

A storm in 1914 brought massive waves that reached the tower's balcony and temporarily extinguished the light for several hours. This event demonstrated the raw power of ocean storms at this rocky coastal location.