The 1 000-ton vessel boarded by some 80 crewmen was captured by the navy of the DPRK in January Juche 57 (1968) after entering its territorial waters for an espionage mission, at the dictation of the CIA.

After the capture, the United States threatened the DPRK militarily. But it could not but make a written apology in December that year, daunted by the Korean people's staunch position. The vessel has been well known in the world ever since.

The spy ship serves as a reminder of the U.S. persistent military threat to the DPRK.

Preserved inside the ship are what they used for espionage.

The ship was brought to the spot where the U.S. ship "General Sherman" was sunk in 1866 after entering the river.