Słowiński National Park

The park encompasses the Łebsko Spit, extensive lakes (including Łebsko and Gardno), peat bogs, and coastal forests, and its hallmark is shifting sand dunes. The SNP holds the status of a UNESCO Biosphere Reserve—protecting unique aeolian processes and coastal ecosystems. Tourists can enjoy a network of hiking and cycling trails, viewpoints (e.g., Rowokół, Czołpino lighthouse), and museums. When planning a visit, it is worth checking which trails are subject to a fee during the season and the current rules for accessing nature (e.g. moving around the dunes only along designated routes). 

Practical:
Official information, maps, tickets online: spn.gov.pl.