By Terry Tomalin

People packed the pier on Jacksonville Beach on that warm evening in the spring of 1942. As the war in Europe raged, Americans still felt safe at home. Then, without warning a tremendous explosion echoed across the water.

At first, everybody thought two oil tankers had collided in the busy shipping lanes just miles from shore.  Freighter traffic was a common sight as the United States struggled to keep its ally Great Britain supplied with oil, aluminum and other goods necessary for the fight against Nazi Germany.

Then a German submarine surfaced between the packed pier and burning ship, finishing the stricken vessel off with its deck gun. The sinking of the Gulfamerica – an 8,000-ton steam tanker on its maiden voyage from Port Arthur, Texas, to New York City – just miles off the crowded boardwalk is probably the most famous battle in a U-Boat war few know was waged so close to Florida's shores.

The waters of the Gulf of Mexico and Atlantic Ocean are littered with rusting hulks of freighters and the submarines that sank them in the opening months of World War II. These war relics are the favorite haunts of recreational scuba divers, but few know the full story of the last time hostile warships patrolled American waters.

One week after the Japanese attack on Pearl Harbor, five German submarines left their secret bases in the Bay of Biscay in the North Atlantic and set sail for the East Coast of the United States. It took two weeks for the U-boats to get within sight of land, and when they did, their captains were surprised to see the lights of the coastal cities shining brightly.

There was still no blackout, so ships running against the coastline made easy targets. The German code name for the coordinated attack was Paukenschlag, or Drumbeat. And before it ended on Feb. 5, the five "sea wolves" had sunk 25 ships. The Germans returned to France, refitted and re-armed, then returned later that spring. For a while, early in the U-boat war, the Germans sank an average of 100 ships a month.

The sinking of the Gulfamerica was not only unique because of its close proximity to land, but also to the boldness and subsequent chivalry of the German captain, Reinhard Hardegan. The young U-boat commander had sunk nine Allied ships on his first sortie into U.S. waters.

When he spotted the Gulfamerica five miles off Jacksonville Beach on April 11, 1942, the tanker loaded with 101,500 barrels of furnace oil was not running a zigzag course, a standard for ships in a combat zone. Hardegan's U-123 fired one torpedo, which hit amidships and set the tanker ablaze.

The captain wanted to conserve torpedoes but knew he had to ventilate the hull to make sure the tanker sank. Noting the innocent civilians on shore, Hardegan positioned his U-boat between the burning freighter and the beach and opened fire, knowing any stray shells would land in the open ocean.

The Germans sank their first ship in the Gulf of Mexico on May 4, 1942, when U-507 torpedoed the freighter Norlindo, west-northwest of Key West. U-boats sank an average of about one ship per day that month. A headline from the July 19, 1942 edition of the St. Petersburg Times proclaimed "Ship Toll Passes 400-Mark."

An accompanying photograph shows a burning ship with the caption, "Flames and smoke burst from a sinking U.S. cargo ship, which was torpedoed by an enemy submarine in the Gulf of Mexico while lying close to shore and blacked out. Fifteen crewmen struggled to a partially burned lifeboat and escaped, but 27 perished."

That same morning, while St. Petersburg residents read about the freighter, another ship had troubles of its own. The Baja California, a Honduran-flagged steam merchant owned by a subsidiary of the United Fruit Company, was en route from New Orleans to Puerto Barrios, Guatemala, when it was hit by two torpedoes fired from the U-84.

The freighter, carrying a load of military vehicles, tobacco and several tons of glassware, turned on its side and sank in 10 minutes about 40 miles northeast of Rebecca Shoals. According to one account of the sinking, three men were killed and 10 wounded in the initial attack. But while the stories of the men who served aboard the Baja California may be lost to history, the ship still has a tale to tell.

Scuba divers can still find old bottles around the wreck, especially after a storm. According to the ship's manifest, the Baja carried a general cargo, which included tobacco and cotton, as well as military vehicles and several tons of empty bottles.

As the ship was sinking, the bow section split off and now rests about 50 feet from the rest of the wreck. Salvagers removed the ship's 14-foot steel propeller years ago. The .50-caliber machine gun that was mounted on its foredeck also is gone, but the 4-inch deck gun that guarded the stern is intact.

Dive charters from Fort Myers Beach make regular trips to the Baja California. The wreck lies midway between Fort Myers Beach and the Dry Tortugas in 115 feet of water, which makes it a trip only for "advanced" divers. The Baja is completely encrusted in barnacles, sea anemones and other marine life, the decks having collapsed decades ago.

If you dive the Baja today, you undoubtedly will encounter large schools of amberjack that seem to serve as silent sentinels for the sunken ship below. The Baja also has a resident barracuda population, which can make it difficult for spear fishermen to get their catch to the surface.

If you make it all the way down to the wreck, you can see what’s left of the jeeps and trucks that were lost in the sinking, as well as 1940s-era glass bottles.

The Baja isn't the only World War II relic accessible to divers. The Empire Mica, sunk off the Panhandle, as well as a half-dozen wrecks off Canaveral and Fort Pierce, also are popular diving destinations. The U-boats -- and there are three known to have sunk off Florida's coast -- tend to be in deeper water and, as a result, are visited only by technical divers trained in the use of mixed gas.

The Germans sank their last ship in the Gulf of Mexico on Sept. 4, 1942, but the War in the North Atlantic continued into the following year. Eventually the convoy system, combined with the use of attack aircraft and fast surface vessels, turned the tide against the Germans.