12th-14th century AD, Crusades period. Iron, 3 1/8” length plus the tang. Medially ridged triangular form with flared foot to seat to the shaft. Each side with two holes for binding incendiary material. The arrow was lit then fired into a castle or fortress. Both had considerable flammable components including thatched roofs as well as the remnants of animal feed and bedding. The opportunities for starting a fire were greatly multiplied by the use of many such arrows. This example was probably fired from a ballista owing to its weight and the range at which it was fired.