Roman Catholic Diocese of Sion Roman Catholic Diocese of Sion The Diocese of Sion (, , ) is a Roman Catholic ecclesiastical territory in the canton of Valais, Switzerland. It is the oldest bishopric in the country and one of the oldest north of the Alps. The history of the Bishops of Sion, of the Abbey of St. Maurice of Valais as a whole are inextricably intertwined. The see was established at Octodurum, now called Martigny, the capital of the Roman province of Alpes Poeninae. The first authentically historical bishop was Saint Theodore/Theodolus (died in 391), who was present at the Council of Aquileia in
Sion Causeway Sion Causeway Sion Causeway (also known as Duncan Causeway) is a major causeway in Bombay, India which connects Sion in Bombay with Kurla in Salsette. The construction of the causeway began in 1798 and was completed in 1805 by Jonathan Duncan, Governor of Bombay (1795–1811), at a cost of £5,037 (Rs. 50,370). In 1826, its breadth was doubled and improved at a further outlay of £4,000 (Rs. 40,000) A volcanic tract extends from Carnac Bunder to Sion Causeway, and forms the entire of the chain of hills bordering the north-eastenn end of the island from the Sewri Fort to Sion.