From April to October, steamers operated by Sächsische Dampfschiffahrt plough up the Elbe several times daily between Dresden and Bad Schandau, stopping in Rathen, Königstein and other towns. The entire one-way trip takes 5½ hours and costs €25 (concession €18). You can do the entire trip or hop aboard along the way.
Passenger ferries (bicycles allowed) cross the Elbe in Stadt Wehlen, Rathen and Königstein, though only the ferry in Rathen is very regular.
From mid-April to October, a bus service operated by Frank Nuhn Freizeit und Tourismus shuttles between Königstein, Bad Schandau and Mezni Louka in the Czech Republic three times daily (full trip €6). Buy tickets from the driver.
Towns are linked to Dresden and each other by the B172; coming from Dresden, it’s faster to take the A17 and pick up the B172 in Pirna. There are only three bridges across the Elbe: two in Pirna and one in Bad Schandau.
The Dresden S1 S-Bahn line connects Bad Schandau, Königstein and Rathen with Dresden, Pirna, Radebeul and Meissen every 30 minutes. Bad Schandau is also a stop on long-distance EC trains travelling between Hamburg and Vienna.