 Between the two termini, there was a ridge of high ground at Smethwick, which was crossed by building a flight of six locks at Smethwick, and another six at Spon Lane.Both ends were at what became known as the Birmingham Level of above sea level, but the locks raised the level by to .When building of the Birmingham Canal main line continued towards Wolverhampton and the Staffordshire and Worcestershire Canal at Aldersley Junction, Spon Lane Junction was formed half way down the Spon Lane flight of locks, at the Wolverhampton Level of .