If you cannot spend the night, Long Hai beach out of Vung Tau is not a great day trip. It's a 30 minute scooter ride from Vung Tau. There is what looks like a nice beach, with virtually no tourists, a local hang out. This seemed great until I walked on the beach. Absolutely trashed, filthy with garbage. Not a nice place to hang out. The resorts are apparently OK. Staying in Vung Tau might be a better option if you only have a day to spend. Also, there are no taxi's available once you get there to return to Vung Tau, you have to persuade a vendor to use their cell phone to call for you.