Cheval de frise

In the anti-cavalry role the cheval de frise typically comprised a portable frame (sometimes just a simple log) with many projecting spikes.

[3][4] Barbed wire chevaux de frise were used in jungle fighting on the South Pacific islands during World War II.

The cheval de frise was adopted in New York and Pennsylvania during the American Revolutionary War as a defensive measure installed on rivers to prevent upriver movement by enemy ships.

During the Peninsular War, at the Siege of Badajoz (1812), a cheval de frise was used to fill a breach in the town wall, allowing the French to inflict heavy casualties on the British storm troops.

[16] In November 2012, a 29-foot (9 m) spike from a cheval-de-frise was recovered from Delaware off Bristol Township; it was also believed to be from the Revolutionary era installation at Philadelphia and freed up by Hurricane Sandy earlier that fall.

[17] A small promontory on the north-east Essex coast in the United Kingdom (UK), between Holland Haven and Frinton-on-Sea, was named Chevaux de Frise Point.

A Confederate cheval de frise at the Fort Mahone defenses during the siege of Petersburg
The "knife rest" or "Spanish rider" is a modern wire obstacle functionally similar to the cheval de frise , and sometimes called that.
Chevaux de frise , according to the later use of the term, could include broken glass studding the top of a wall in a nineteenth-century fort.
Hessian map showing the placement of chevaux de frise in the Delaware River in 1777
Outline showing the structure of a Cheval de frise for river use:
Illustration A: Side view;
Illustration B: Top view