When visiting Saigon there are several excursions you can do. The most popular one day tour, is a visit to the Cu Chi Tunnels and the Cao Dai Temple.
The Cao Dai Temple is 60 miles (100 km) from Saigon. Although some guides say it is not worth the long trip, I disagree. If you only have half a day free, reserve a Cu Chi Tunnels tour. But if you half a full day, visit both. First thing in the morning you will get on a minibus and go to the temple. You will get on time to visit the temple and see a ceremony from one of the balconies (next photo). Later the minibus will take you to the Cu Chi Tunnels.
The Cu Chi Tunnels show the tenacity of Vietnamese people. The first tunnels were built during the French War, but the longest ones were dug during the American-Vietnam War. The tunnels were several hundred miles long. Some of the Tunnels stretched from Cu Chi to the Cambodian border. The tunnels were used to attack the Americans. The Cu Chi area has the doubtful honor of being the most bombed land on earth. If you visit the Tunnels you will be shown the craters of some of the dropped bombs.