Germany's railways offered a month of unlimited rides for $9. Here's what happened

Walking from Brühl's town center to the train station, I passed a UNESCO World Heritage site. The 18th-century Augustusburg Palace -- one of Germany's earliest examples of Rococo architecture -- draws visitors from all over the world. Brühl itself, 11 miles south of Cologne, has a pretty pedestrianized main street, acres of parkland and the Max Ernst Museum -- the artist was born here.