Welcome. You are standing in Vienna's Innere Stadt, the old city, on the small square where Kirche Maria am Gestade lifts its narrow Gothic tower above you. If you have spent the day among Baroque domes and grand imperial facades, this building is going to feel like a surprise. Published descriptions call it one of the oldest churches in Vienna, and one of the few surviving examples of Gothic architecture in a city that later dressed itself almost entirely in a different style. Travel writers have long loved its nickname too: the church of the Danube boatmen. What is well established is this. The church is dedicated to the Virgin Mary. Its Gothic nave was built between 1394 and 1414, while the choir includes older medieval fabric. Some popular accounts push the story much further back, to a wooden church in the ninth century, but that earliest phase is tradition rather than documented fact. Treat it as a lovely possibility, not a proven date. Over the next few minutes we will follow three threads: the river that gave the church its name, the stone you can see above your head, and the people, sailors, fishermen and painters, who kept this place alive. Let us start with the water.