The Battle of Peralonso (Spanish: Batalla de Peralonso), also known as the Battle of La Amarilla or the Battle of La Laja, was a major battle in the Santander Campaign of the Thousand Days' War in Colombia. It was fought between the Conservative government and the Liberal rebels between 15 and 16 December 1899, ending in an important Liberal victory. The Liberal rebels had suffered a series of major defeats culminating in the failed attack on Bucaramanga on 13 November. Afterward, the Liberal forces splintered into three autonomous forces, led by Rafael Uribe Uribe, Benjamín Herrera, and Justo L. Durán, but they first regrouped in Cúcuta. The autonomous rebel armies shifted to new positions on and around the heights of , north of Cúcuta and close to the border with Venezuela.