Sassnitz is the main town of the Jasmund peninsula — a fishing and ferry port built into the cliffs at the southern end of the chalk coast. It is less polished than Binz or Sellin, more working and weather-beaten, and makes a good base for the national park.
The harbour is the centre of things. The HMS Otus, a decommissioned British submarine moored at the pier, is open to climb through and is genuinely interesting. The smoked-fish stalls along the harbourside sell mackerel and herring straight out of the smokers. The Stadthafen sits below the old town, which climbs the cliff face; the suspension bridge, the Stadtschlucht, links the two.
The cliff-top Hochuferweg trail starts at Sassnitz and runs north to the Königsstuhl — the best way into the national park on foot.