We stayed at Cabana Bay. We saw shuttles dropping people off at the entrance, which has a security guard and still a good distance of a walk to where you give your tickets, get fingerprinted and get your wristband.
very good question, because everyone is bused over from the main parking garages at UNIVERSAL like miles away.. Id guess (and might be wrong) that you could get dropped off at Cabana Bay and take the sidewalk to Volcano Bay. I know their guests are able to walk from their hotel.
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