Hercules

The ships in our park's collection have been moved temporarily due to the Hyde Street Rebuild Project. They are now located at the Mare Island Naval Shipyard. Visitors are not currently allowed on the ships, but can view them from Mare Island. When the Hyde Street Pier rebuild is finished, the ships will be moved back to Hyde Street Pier.
 
the steam-tug Hercules is moored to a dock while workers wearing life jackets work on deck

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Hercules is a steam powered tug built for ocean towing. The 151-foot ship, of riveted steel construction, still contains her original triple expansion steam engine. Built on the East Coast in 1907, she towed her sister ship from Camden, New Jersey around South America to San Francisco. Hercules also towed sailing ships, disabled vessels, barges, log rafts, a cassion (a steel structure used for closing the entrance to locks) for a dry dock at Pearl Harbor, and a caisson to help build a Panama Canal lock. The tug usually carried a crew of three firemen, three oilmen, a chief and two assistant engineers, three deckhands, cook, two mates and a captain.
 

Hercules Quick Facts

  • Length: 151 ft

  • Beam: 26 ft

  • Draft: 18 feet aft, 10 feet forward

  • Gross Tonnage: 409

  • Engine: 3 cylinder, triple expansion

  • Cylinders: 17", 24", and 41" with 30" stroke. 500 Indicated Horsepower (ihp)

  • Fuel Type: Oil Fuel

  • Boiler: Scotch marine fire tube. 16' diameter, 11' 9" long. Four oil-burning furnaces

 
Black and white image of tugboat Hercules
Hercules at John H. Dialogue's Shipyard in Camden, New Jersey, January, 1908

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Long Tows on the Open Ocean

John H. Dialogue and Son, of Camden, New Jersey, built Hercules in 1907. She had been ordered by the San Francisco-based Shipowners’ and Merchants’ Tugboat Company, to join their Red Stack fleet (named for their red-painted smoke stacks). When completed, Hercules towed her sister ship, the Goliah, through the Strait of Magellan to San Francisco. Both vessels were oil-burners; Goliah carried fuel, water and supplies for her sister.

Hercules towed barges, sailing ships and log rafts between Pacific ports. Because prevailing north-west winds generally made travel up the coast by sail both difficult and circuitous, tugs often towed large sailing vessels to points north of San Francisco. In 1916, Hercules towed the C. A. Thayer (another of San Francisco Maritime National Historical Park’s historic fleet) to Port Townsend, Washington. The trip took six days. She also towed the Falls of Clyde, now a museum ship in Hawaii. On trips back down the coast, Hercules often towed huge log rafts, laden with millions of board feet of Northwest timber, to Southern California mills. At other times, Hercules towed barges of bulk cargoes between other West Coast Ports, and to Hawaii. During the construction of the Panama Canal, she towed a huge floating caisson (a steel structure used for closing the entrance to locks) to the Canal Zone.

In her deep-sea days, Hercules usually carried a crew of fifteen-enough manpower for her Engine Department to stand three watches while underway. The deep, narrow hull made life uncomfortable at times, because it rode low in the water, and the main deck was often awash. However, the food was good and, for an experienced hand, the work was steady. Tugboat captains were generally well-paid and highly respected, for it took considerable experience to bring a tug and a heavy tow through high seas in bad weather--and good judgment to navigate the shallow bars and narrow entrances of West Coast ports.

 

Bay Tug

Hercules was eventually acquired by the Western Pacific Railroad Company. Her career changed significantly; she no longer served as an ocean-going tug, but shuttled railroad car barges back and forth across San Francisco Bay. She worked until 1962, when changing transportation patterns (the decline of the railroads) and the introduction of diesel-powered tugs sealed her fate.

 

Restoration

Hercules avoided the scrap yard, but languished until the California State Park Foundation acquired her for the San Francisco Maritime State Historic Park, in 1975. The National Park Service took over the task of her restoration in 1977, and in 1986 she was designated a National Historic Landmark. Hercules has been documented as part of the Historic American Engineering Record's Maritime Record.

 
Xplore Timelooper App - Hercules Steam Tug
Xplore Timelooper App - Hercules Steam Tug

Xplore Timelooper

Xplore Hercules Steam Tug

Come explore the Post-Victorian wonderland of steel and steam aboard this 1907 tugboat with the free Xplore Timelooper App.

Last updated: June 6, 2025

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Contact Info

Mailing Address:

2 Marina Boulevard,
Building E, 2nd Floor

San Francisco, CA 94123

Phone:

415 447-5000
Visitor Center staff can be reached every day from 10 AM to 5 PM.

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