My wife and I want to plan a trip to one of the Malaysian islands but want a little more information on what they are like. We want to be away from crowds and somewhere more relaxing and secluded. Which island would be the best for this?
I just returned from Malaysia in January and spent there entire month on both Borneo and Peninsular Malaysia. I had a chance to visit and spent few days on both Langkawi and Penang, but for what you want is Langkawi definitely better option. It has smaller crowd, beautiful beaches, it's duty free zone so you can enjoy beer 2-3x cheaper than on a mainland and you can do other things like mangrove kayaking or exploring the entire island and its hidden gems on a scooter (rental cost me $12/day). If you are a scuba diver, you can go diving to Pulau Payar Marine Park. Langkawi has as well something called rotating night food market which takes place every day somewhere else on the island and is really worth visiting as you can taste different delicacies of Malaysian cuisine and it certainly has its vibe.
Moreover, Langkawi is the only UNESCO-endorsed Geopark in Southeast Asia. I was told by a local guide that they were recently warned by UNESCO to stop any bigger scale resort development on the island or they will lose the status.
If you really want to visit Georgetown (Penang), which I think is worth your time for 1-3 days, you can do so as a day or weekend trip from Langkawi.
To give you a better idea, feel free to check my galleries:
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I would recommend you to Langkawi Island. This island is very picturesque. It's wild nature and amazing beaches made our trip unforgettable.
I would also advise you to rent a car there. Last year we book a car at RentalCars24H - Langkawi Island. You can pick your rental car at the Langkawi airport and go to any spot of the island.