Going all the way to Tay Ninh to visit the Great Cao Dai Holy See, a place of pilgrimage for quite a few Vietnamese Southern followers of Caodaism. In time of the noontide prayer service, you will join a peculiar but solemn ceremony with the congregation attired in lively red, yellow, blue and white and chanting religious hymns, followed by a delicious lunch in Tay Ninh. Then return to Ho Chi Minh City, with a stop at the “underground village” in Cu Chi district, which was used by the guerillas during the Vietnam War