Monkey Island near Nha Trang – Probably don’t go
One of the more unusual and interesting attractions in Vietnam is locally known as Lao Island, but more famously known to visitors as Monkey Island. It’s about 10 km from the heart of Nha Trang, and it can be visited in several different ways. If your time is very limited then an all-day boat trip with a quick Monkey Island visit isn’t a bad way to go, but if you want to spend more time there to enjoy more than just the shortest of visits then it’s cheap and easy to do yourself. Almost all prices in Nha Trang are very low by Western standards, and the DIY Monkey Island trip is no exception.
Important note: Monkey Island is accused of animal cruelty and there is a campaign to have it shut down
Starting in 2018, Monkey Island has come in the sights of animal rights groups who accuse them of animal cruelty. I have no way of verifying this myself and it's been more than 8 years since I've been there, so I will defer to them. I visited twice in 2010 and didn't witness anything bad, but that was a long time ago. I can no longer help promote the place and my information might be out of date anyway, so I'm removing it.