Any ads in the ABC 7 clip above are placed by the broadcasting station. Longshore and Shipping News does not advertise.

After lowering some of the electronic antennas, the Benjamin Franklin passed under the Golden Gate Bridge Thursday morning, with about 20 feet to spare.

The ship is a quarter-mile long, making it the biggest ship to ever dock at an American port. The megaship can hold up to 18,000 20-foot shipping containers. The largest ships serving the U.S. can carry 14,000 containers.

Ships like this are actually common on routes between Asia and Europe. Overall, they cost less to operate, use less fuel and they pollute less.

The Port of Oakland has been preparing for this for years. Oakland is one of only a handful of U.S. ports that can receive megaships, which carry large loads of cargo.

The port has invested millions of dollars in changes, including dredging berths and channels to depths of 50 feet, raising the heights of cranes and modernizing marine terminals, port officials said.

Last month, port officials announced they will be raising the height of four gantry cranes at the Oakland International Container Terminal by 26 feet to accommodate megaships. The $13.95 million project is scheduled to begin in April.

More at ABC 7