It is a bit surprising that people can spend lots of money producing such a well-made sign but not bother to get the English right.
The analysis of this English raises some questions. Does areas have a spurious ‑s suffix? Or is it a case of confusion between this and these?
My feeling is that the former analysis is better: the intended message is supposed to refer to 'this recreational area', but the sign-writer used the plural areas instead. However, I have also come across this used with plural nouns. It seems that there is no clear distinction between this and these in Brunei, possibly because many speakers do not differentiate between long and short vowels.