Sound
- Kattegatt
A strait of the North Sea between Jutland and Sweden; connects with the North Sea through...
- Skagerrak
A broad strait of the North Sea between Jutland and Norway.
Also contains
- Orkney Islands
An archipelago of about 70 islands in the North Atlantic and North Sea off the northeastern...
- Zuider Zee
A former inlet of the North Sea in the northern coast of the Netherlands; sealed off...