The six marble columns marking Chapultepec park's eastern entrance commemorate the ‘boy heroes,’ six young cadets who perished in battle. On September 13, 1847, 8000 US troops stormed Castillo de Chapultepec, which then housed the national military academy. Mexican General Santa Anna retreated before the onslaught, but the youths, aged 13 to 20, chose to defend the castle. Legend has it one of them, Juan Escutia, wrapped himself in a Mexican flag and leaped to his death rather than surrender.