The tripto catalogue lists 15 national parks – from the North Sea coast to the Alps. Almost all are free to enter; you only pay for visitor centres, treetop walks and parking.
Saxon Switzerland National Park on the Elbe has about 400 km of trails among sandstone rocks, table mountains and gorges, including the Schrammsteine and the Kuhstall. Berchtesgaden National Park is Germany's only Alpine national park, with Königssee, St Bartholomew's and the Watzmann. Bavarian Forest National Park is the country's oldest; the animal enclosure and the Hans-Eisenmann-Haus are free, and the treetop walk costs €13. Jasmund National Park on Rügen, the smallest, shows white chalk cliffs and the Königsstuhl skywalk. The Schleswig-Holstein Wadden Sea is Germany's largest national park and a UNESCO World Natural Heritage Site, and Müritz National Park, with more than a hundred lakes, is the largest on land, home to white-tailed eagles and cranes.
The national parks in the catalogue are spread across many states; Mecklenburg-Western Pomerania has three (Jasmund, Müritz, Western Pomerania Lagoon Area) and Bavaria two.
In practice: allow at least half a day, and several days for the Wadden Sea or Saxon Switzerland. Only go mudflat hiking with a guide and according to the tide tables. Stay on marked trails – core zones require it. The best time is May to October; in autumn, cranes gather around the Müritz.