Welland Canal and crossings are numbered from north to south. The following illustration depicts the profile of the Welland Canal. The horizontal axis is the length of the canal. The vertical axis is the elevation of the canal segments above mean sea level. If assigned by the St. Lawrence Seaway Authority. The original bridges across the fourth canal were numbered in order. Numbering was not changed as bridges were removed. Welland Canal The Welland Canal is a ship canal in Ontario, Canada, connecting Lake Ontario and Lake Erie. It forms a key section of the St. Lawrence Seaway. Traversing the Niagara Peninsula
Welland Canal affiliated with the canal, and was actually used to help transfer cargoes from the lake ships, which were too large for the small canal locks, to the other end of the canal (The Trillium Railway owns the railway's remnants and Port Colborne Harbour Railway). Smaller ships called "canallers" also took a part of these loads. Due to this problem, it was soon apparent the canal would have to be enlarged again. In 1887, a new shorter alignment was completed between St. Catharines and Port Dalhousie. One of the most interesting features of this third Welland Canal was the Merritton Tunnel,