Amid the bustling streets of Ho Chi Minh City, a humble house at 287/70 Nguyen Dinh Chieu Street, District 3, quietly preserves a significant piece of history — the secret weapon bunker of the biet dong Sai Gon, a special force unit of the Vietnam People's Army that operated during the Vietnam War. This site once hid over two tons of weapons, prepared for the attack on the Independence Palace during the 1968 Tet Offensive.