Taller than Oakland’s storied Tribune Tower building, valued at $30 million, the largest container cranes ever to enter the city are expected to arrive at the Port of Oakland this week.

The three mammoth cranes, among the country’s largest, will soon be unloading cargo from massive ships for owner Stevedoring Services of America. Sailing from China, they were due to anchor off the California coast Christmas Eve enroute to SSA’s Oakland International Container Terminal at the port.

They are too tall to fit under the Golden Gate and San Francisco-Oakland Bay bridges with their booms — long poles that lift cargo — fully extended. When raised, the booms will soar more than 400 feet above the wharf. That’s about 100 feet taller than the 20-story Tribune Tower in downtown Oakland.

The cranes were manufactured by Shanghai-based ZPMC. They can lift containers as high as 174 feet above the dock, reaching 225 feet across ship decks, according to SSA.

This trio of mammoth shipping container cranes, among the largest in North America, is headed from China on the way to Oakland. (Photo courtesy of Port of Oakland)

The port’s existing cranes have long been the stuff of urban legend. Residents love to speculate that the tall leggy structures visible from many points in the East Bay inspired the snow walkers in the George Lucas film, “The Empire Strikes Back.” Insiders connected with the film routinely deny any connection.

In real life, the new cranes are predicted to provide an economic boost for the city and the entire area.

“These cranes will keep the Port of Oakland competitive so that we can continue to attract the largest vessels calling North America,” said Port of Oakland Executive Director Danny Wan in a statement. “Ultimately, bigger cranes at our waterfront translate into maritime and related jobs for the region.”

Every 1,000 containers represent eight jobs. The Port of Oakland presently has around 33 ship-to-shore cranes serving more than 1,500 ships annually, according to the port’s website. Together with its business partners, the port supports more than 84,000 jobs.

“Taller cranes are needed for efficiently handling cargo that arrives on ultra-large container ships,” said SSA Containers President Edward DeNike. “This new infrastructure is a commitment to the port that we will continue our maritime business at Oakland well into the future.”