Morning: A half-day city tour of dynamic Ho Chi Minh City, still called Saigon by many locals, includes the Notre Dame Cathedral, Old Saigon Post Office, the Chinatown, the former Presidential Palace. Afternoon: Transfer about 30km north-west of Saigon to Cu Chi town. Cu Chi tunnels were used as the base from which the Vietnamese mounted their operations of the Tet Offensive in 1968. The Cu Chi tunnels consist of more than 200km of underground tunnels. This main axis system has many branches connecting to underground hideouts, shelters, and entrances to other tunnels, the tunnels are between 0.5 to 1m wide, just enough for a person to crawl along. Transfer back and overnight in Saigon.