This is one of the postcards I've received through 'Postcard United' (with postcard ID 'CZE-825). I haven't received any more for a while now but I still got way more than received. I wonder if any more are on their way...
This is a famous rail route in Czech Republic, called Posázavský Pacifik. I found some information on this website:
Posázavský Pacifik is the name for a recreational historical route following the Sázava River, which courses through the hilly countryside of Central Bohemia, southeast of Prague. The route’s name originates in the tramping sub-culture. Various cottages along the route were named after places from the Pacific Coast of America.
You can read more on that website, it's quite interesting as well. :)