Who was the last US President to cross the Atlantic Ocean by ship while in office?

Woodrow Wilson became the first U.S. president to visit Europe while in office. In the aftermath of World War I, Wilson, the nation's 28th president, would spend the next six months, on and off, in Europe, the longest time any chief executive would remain abroad.

On 7 July 1945, USS Augusta (CA-31) stood out of Hampton Roads, Virginia, bound for Europe. On board were President Harry S. Truman and his party, en route to attend the "Big Three" conference at Potsdam, Germany. After being escorted through the English Channel by the Royal Navy, Augusta arrived at Antwerp, Belgium, on 15 July. President Truman left the ship there to continue his trip by road and air.

When the Potsdam Conference ended on 2 August, Truman flew to England, rejoining Augusta at Plymouth, where he was visited by King George VI. That afternoon, the cruiser went back to sea. She arrived at Newport News on 7 August, where the President disembarked to return to Washington, DC.