I heard about the same occuring in Los Banos, Laguna but I haven't experienced it until this. We parked our car beside the KM34 SB13 road marker, put in on neutral and then voila! our car moved backward on the downhill slope.
They call this occurence the gravity hill or magnetic hill. We were awed by what we saw and talked much about it after the trip. Fascinating as it is, though, science (or is it?) explains it as a mere optical illusion. According to Wikipedia, "...Objects one would normally assume to be more-or-less perpendicular to the ground (such as trees) may actually be leaning, offsetting the visual reference."
Down goes my excitement....Oh well, whatever it is, it still makes for a good tourist attraction. Check it out for yourself!
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