Abermule is located on the River Severn and the Montgomeryshire canal. The canal is very close to the river. The village was the site of the Abermule train collision on 26 January 1921, which killed 17 passengers, including the Cambrian Railways chairman, Lord Herbert Vane-Tempest of Machynlleth. The crash arose from misunderstandings between staff which effectively over-rode the safe operation of the Electric Train Tablet system protecting the single line. A train departed carrying the wrong tablet for the section it was entering and collided with a train coming the other way.