North Sea marinas

The North Sea borders England/Scotland, Norway, Denmark, Germany, the Netherlands, Belgium and France; it connects to the English Channel via the Dover Strait and to the Baltic via the Skagerrak/Kattegat.

South of roughly 53° N depths are generally <50 m, while the Norwegian Trench in the north exceeds 700 m. Tides and tidal streams dominate passage-making: the Wadden Sea typically sees 1.5–4 m ranges, and the Pentland Firth experiences streams of 7–8 kt with local peaks around ~16 kt. Prevailing winds are westerly; the share of ≥Force-7 winds is about 20% in January, dropping to 2–4% in July.

Coastal sea-fog is common in spring and summer along the east coast, sharply reducing visibility. 

The Dover Strait is among the world’s busiest maritime passages (~1,300 ship crossings per week in 2023); an IMO TSS, Channel VTS (CNIS) and the CALDOVREP reporting scheme are in force. 

In the German Bight/Wadden Sea, shifting shoals and migrating channels are well documented; mariners rely on frequent navigational warnings.

The sea hosts extensive offshore infrastructure—wind farms and oil/gas platforms—with 500-m safety zones around installations.

Offshore wind density is especially high off Belgium, the Netherlands, Germany and the UK (see project lists and maps).

Water temperatures vary widely: around 6 °C in the north in winter, rising to ~18 °C in the south in August.