A spit is a deposition landform connected to the coast that projects into open water. Spits typically form where longshore ocean drifts meet a section of land with contours greater than 30 degrees. Bent sharply and receding perpendicularly from the shore, these currents lose momentum and deposit sediment in their wake down the shoreline. Growing spits shelter backwaters from wind and waves, enabling salt marshes to form.
The Dungeness Spit in Washington State is one of the longest in the world at over 5 miles.