Photos of the SS United States being pulled by a 140-foot tugboat prompted many to ask how the move was even possible.

After months of delays, the historic SS United States ocean liner finally moved out of Philadelphia today on a new voyage as it prepares to become the world's largest artificial reef off the Florida coast in the Gulf of Mexico.

The SS United States has completed its voyage from Philadelphia to Mobile, Alabama, where it will be prepped to become part of the world's largest artificial reef.

Crews will spend about six months cleaning the 1,000-foot vessel and removing hazardous materials as they prepare it to eventually be sunk off Florida's Gulf coast.

Efforts to save the SS United States from being sunk as an artificial reef are ongoing, with appeals for federal intervention.