The Swin was used by barges and leisure craft from the Essex rivers, and coasters and colliers from Hull, Great Grimsby, North East England, Edinburgh and other similar sets of trading ports.

Ballantyne wrote: The channel ... was the Swin, which, though not used by first-class ships, is perhaps the most frequented by the greater portion of the coasting and colliery vessels, and all the east country craft.

The traffic is so great as to be almost continuous; innumerable vessels being seen in fine weather passing to and fro as far as the eye can reach.

Approaching from the northeast craft enter the East Swin between NE Gunfleet and Sunk Head Tower buoys.

[4] Halfway along this part, at the Maplin Approach buoy, deeper draught vessels need to pass through to the Middle Deep centred on 51°39′N 01°10′E / 51.650°N 1.167°E / 51.650; 1.167.