evidence: Nicknamed the schwäbische Meer (Swabian Sea), Lake Constance – Central Europe’s third-largest lake – straddles three countries: Germany, Austria and Switzerland. Formed by the Rhine Glacier during the last ice age and fed and drained by that same sprightly river today, this whopper of a lake measures 63km long by 14km wide and up to 250m deep. There is a certain novelty in the fact that this is the only place in the world where you can wake up in Germany, cycle across to Switzerland for lunch and make it to Austria in time for afternoon tea, strudel and snapshots of the Alps. [...] This exuberant, powder-pink Cistercian abbey church is one of Lake Constance's architectural highlights and a popular pilgrimage destination. It was built…