 The building that is now the cathedral was built as a church between 1727 and 1750 by the businessman Henri Schuller (or Shuler) (whose son was later a canon here) to plans by Jacques Philippe Mareschal, king's engineer at Strasbourg.It was built of red sandstone excavated from the quarry at Offemont, three kilometres from Belfort.Although the church opened for worship in 1750, the north tower was not completed until 1845.