Where the North Sea Begins

The North Sea is a marginal sea of the Northeast Atlantic. Its southern boundary—where it "starts"—is conventionally drawn at the Strait of Dover (Pas de Calais), the narrowest part of the English Channel, between South Foreland (Kent, England) and Cap Gris-Nez (Pas-de-Calais, France).

From there, it extends northeastward, bounded by:

• West: Great Britain (England, Scotland)
• East: Norway, Denmark, Germany, Netherlands, Belgium
• North: Shetland/Orkney → Norwegian Sea (arbitrary line at 62°N)

It connects to the Atlantic via the English Channel (southwest) and the Norwegian Sea (north). The Kattegat/Skagerrak link it to the Baltic Sea.