The Welland Canal has been the focus of plots on a number of occasions throughout its existence. However, only two have ever been carried out. The earliest and potentially most devastating attack occurred on September 9, 1841 at Lock No. 37 (Allanburg) of the First Welland Canal () (approximately 180 m north of today's Allanburg bridge), when an explosive charge destroyed one of the lock gates. However, a catastrophic flood was prevented when a guard gate located upstream of the lock closed into place preventing the upstream waters from careening down the route of the Canal and causing further damage and possible injury or loss of life. It was suspected that Benjamin Lett was responsible for the explosion.