Marlboro, Alberta was named when a large deposit of Marl was discovered there on May of 1911. Marl or Marlstone is a mixture of calcium carbonate and clay and was used in the manufacture of cement and bricks. It is no longer used for that purpose as it has been replaced by limestone. In 1913, the Marlboro Cement Plant, Alberta's first cement plant, was built by the Edmonton Portland Cement Company. Marlboro was located 25 kilometers west of Edson, Alberta. The site was chosen for its proximity t