I have also mapped some places that I may see in Saigon (HCMC):
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The following shows the location of the Cao Dai Temple in Tay Ninh and the Cu Chi Tunnels. According to LP, these two are included in a $5.00 day tour which I may opt to join on my return from PP or SR, if I have time left.
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But since I have only a day left on my itinerary, I will choose between Cu Chi/Cao Dai or Mekong. I think Mekong is better but I have to consider the weather too. So I'll decide when I'm there. But for Mekong tour, I'll choose the Cai Be-Vihn Long Day Tour. Here's the map for Mekong:
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