A lava field.
A rough and rocky district, especially in a volcanic region.
On this route was situated the pedregal, which is a field of volcanic rock of very uneven surface.
Worth was ordered to cover San Antonio, Quitman to hold San Augustin, and Pillow to march over the pedregal, while Twiggs was to cover and support Pillow’s movement.
Once he crossed the pedregal, a region where an old lava flow had cooled, and which presented to his feet numerous sharp edges like those of a knife.
The Texan Star The Story of a Great Fight for Liberty
The word ‘pedregal’ comes from a Spanish word meaning ‘a stony place’, ultimately from ‘piedra’ (‘stone’).