There isn't much of anything to see or do around the Petchburi Subway station. In fact, unless you're heading to or from the airport via the Airport Link, there isn't really any reason to go there at all.
It's worth noting that to get from the subway station to the Airport Link terminal requires you to cross an often busy street and a set of railroad tracks. There is not, as yet, any dedicated pathway or elevated link, and even the signage is poor. You wouldn't want to make the trip carrying a lot of luggage.
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