I have always visited Bai Yok tower (the tallest skyscraper in Bangkok, Thailand) every year since 4-5 years ago. Panoramic view of Bangkok, and one free drink, for 300 baht (~ USD10.00) are simply irresistible. This year, I moved up from 77th floor to 81st floor. I just realized that 81st floor gives a better vantage point, not because it is higher up, but window frames do not obstruct the view as much as 77th floor.
Since many people queried me about Bai Yok, you can reach Bai Yok hotel (yes, it's a hotel) by Airport Link train. USD10 will get you to the observation deck. USD20 will get you to the observation deck, plus a buffet. USD30 gives you an open-air buffet where you can enjoy Bangkok night in its full glory. If you want to stay in the hotel, that will be USD60.
My other deviations:
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