An iconic Martha's Vineyard's lighthouse is moving from its rapidly eroding cliffside perch.

The Gay Head Lighthouse, a 160-year-old beacon that's among the most endangered historic landmarks in the United States, is expected to begin a multi-day trek inland on Thursday.

Workers already have hoisted the 400-ton brick-and-mortar lighthouse about six feet off the ground and placed it on a wood-and-steel frame for the move.

Over the next few days, it is expected to travel along steel beams a total of about 129 feet, arriving at its final destination as soon as Saturday.

The project is being paid for with about $3 million in donations and grants. The present lighthouse has stood on the clay and sandstone cliffs since 1856. A beacon has existed there since 1799.