The last Liberty ship of D-Day’s invasion fleet still cruises San Francisco Bay

The SS Jeremiah O’Brien

The SS Jeremiah O’Brien made 11 dangerous round trips across the English Channel after D-Day, hauling troops and supplies to Normandy beaches while dodging enemy attacks.

Built in just 56 days in Maine, this Liberty ship became a workhorse of the invasion, carrying everything from ammunition to food that kept Allied forces fighting. She’s now the only surviving ship from that massive armada with over 7,000 vessels.

Here’s her story, preserved at San Francisco’s Pier 35 where you can walk her decks today.

Joining Operation Neptune’s Massive Naval Armada

The O’Brien joined nearly 7,000 ships in the largest sea invasion force ever assembled on June 6, 1944. This fleet formed Operation Neptune, the naval part of Operation Overlord – the Allied invasion of Nazi-occupied France.

Grace Line ran the ship for the War Shipping Administration. Merchant Marine crew handled sailing and engine duties while Navy Armed Guard sailors operated the guns for protection against enemies.

The Liberty Ship’s Vital Wartime Mission

Liberty Ships kept Allied forces supplied throughout Europe. Each ship carried about 10,000 tons of cargo at 11 knots across dangerous seas. The O’Brien stretched 441 feet long and 56 feet wide, with a weight of 7,176 tons.

Guns mounted on deck protected this slow-moving target from enemy planes and submarines. Without these workhorse ships, Allied soldiers would have lacked the weapons, vehicles, food, and medicine needed to defeat German forces.

First Channel Crossing Under Threat of Attack

The O’Brien sailed the English Channel through constant danger in June 1944. German submarines and fast attack boats hunted Allied ships in these waters. Lookouts watched for enemy vessels while radar operators scanned for threats.

Navy gunners stood ready at their weapons to defend against attacks. The Germans had filled the Channel with underwater mines that could instantly sink a ship.

Delivering Crucial War Materials to Normandy Beaches

The ship carried troops and war supplies directly to the Normandy beachhead. Her cargo holds were packed with vehicles, weapons, ammunition, food, fuel, and medical supplies. Crew members worked to unload cargo onto barges and smaller boats.

These vessels then brought supplies to shore where soldiers moved materials inland. Each delivery strengthened the Allied position in France.

Braving German Aerial and Naval Threats

German planes constantly threatened ships crossing the Channel. Pilots targeted supply vessels to cut off Allied troops from essential supplies. The German navy used fast E-boats—motor torpedo boats that could attack quickly and escape.

These small, heavily armed boats could strike without warning. Navy gunners manned the O’Brien’s weapons day and night. The ship operated in complete darkness after sunset, with crews navigating without lights to avoid being spotted.

Navigating the Dangerous Waters of the English Channel

Sailors battled the Channel’s rough waters while moving vital supplies. Strong currents, bad weather, and poor visibility made every crossing difficult. Germans kept dropping new mines in the water throughout the invasion.

These deadly devices exploded when ships passed overhead, making each voyage risky no matter which route was taken. Navigation officers carefully plotted courses through cleared paths while staying in touch with escort ships. One wrong turn could lead to disaster.

Completing Multiple Channel Crossings Under Fire

The O’Brien made an impressive 11 round trips between England and Normandy. Each journey brought fresh dangers, with German forces constantly changing their attack methods.

Engine crews kept the steam power system running nonstop throughout these voyages. Sailors worked with little rest as the ship maintained its vital supply schedule. These repeated crossings formed a crucial supply line for Allied advances.

The Merchant Marine Crew’s Heroism

Merchant sailors ran the O’Brien through dangerous waters day after day. These civilian crew members faced the same risks as military personnel but received less recognition. They worked alongside Navy gunners, forming an effective team despite coming from different services.

Engine room workers endured heat, noise, and exhaustion to keep the vessel moving. Long hours and danger became routine as these sailors completed their mission.

Supporting the Allied Push Into Europe

The O’Brien delivered hundreds of tons of supplies with each voyage. These materials directly supported Allied soldiers pushing inland from the beaches toward Paris. Vehicles, fuel, ammunition, and equipment flowed steadily through ships like the O’Brien.

This supply chain made Europe’s liberation possible as troops advanced against German resistance. By June 30, 1944, Allied forces had landed over 850,000 men, 148,000 vehicles, and 570,000 tons of supplies on Normandy’s shores.

Completing the Normandy Mission

The ship finished all 11 Channel crossings despite constant danger. Few Liberty Ships matched this achievement, making the O’Brien special even among similar vessels. After D-Day operations ended, she continued serving in different areas.

Military leaders sent her to the Pacific, where she supported operations against Japanese forces for 16 more months. Her work helped create the Western Front that eventually led to Germany’s defeat.

Visiting SS Jeremiah O’Brien

You’ll find the SS Jeremiah O’Brien at Pier 35 along San Francisco’s Embarcadero. The ship welcomes visitors throughout the year, though admission fees vary by season.

You can explore almost the entire vessel, from the massive cargo holds to the engine room and bridge. The fully restored triple-expansion steam engine—famous for its appearance in the movie Titanic—comes alive during special “Steaming Weekends” typically held monthly.

The ship also offers occasional Bay cruises where you can experience this historic vessel underway.

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