Claim: The Siege of Zamość began on February 25, 1656 and the invaders withdrew on March 1.
Evidence: On February 25, 1656, Swedish troops appeared at the gates of the stronghold. Within a few days, Charles X Gustav realized that capturing Zamość, whose fortifications had been strengthened since 1648, was impossible, and on March 1, the invaders withdrew. 
February 25 – March 1, 1656