Trenches of the Battle of the Jarama Activity · Rivas-Vaciamadrid, Área Metropolitana, Madrid On the Cerro del Telégrafo and the bluffs of the Jarama, forts, parapets, rifle pits and observation posts survive from the battle fought between 6 and 27 February 1937, one of the bloodiest episodes of the war, today accessible on foot. The offensive, launched by the insurgent army to cut Madrid's communications, unfolded chiefly in Rivas-Vaciamadrid, where the caves used by the Republican side can still be seen on the hillside. The Republican troops, scattered at first, regrouped on 15 February under General José Miaja's command into four divisions that managed to halt the advance towards Arganda del Rey; among the combatants were the XI, XII, XIV and XV International Brigades, who fought between the Jarama and Morata de Tajuña. Photo: Wikipedia / Wikimedia Commons (CC BY-SA) What to see and do in Rivas-Vaciamadrid