Spring has arrived, and with it a taste of the sunny, sweltering climate to come. Longer days and warmer rays make my kids thirst for a swimming pool. However, Japan's outdoor swimming season doesn't officially begin for months, and indoor locations such as Tokyo Summerland water park can trigger claustrophobia in the bravest of souls. Places like Oedo Onsen Monogatari in Odaiba can also be a nice getaway for families, but with its focus on the hot-spring experience, this is more a place for adults to relax than for kids to go wild.

That's why I'm grateful for Spa World in Osaka. It is no match for Japan's luxurious onsen retreats, and nor will it replace the loud, jam-packed amusement-park experience my kids prefer come summer. Instead, Spa World serves as a happy medium between the two while we wait for July. Splashing around in its warm waters has always been a pleasure during the bitter cold of January, but it still feels great now, even after winter's sting has retired for the season.

Spa World's attractions are spread over four main floors. The fourth of these is called the European Zone and contains a variety of rooms designed to resemble spas and saunas of the Western world. Two stories up, the sixth floor has an identical floor plan, but with an Asian theme. For example, the first room in the European Zone has a massive hot tub mimicking Rome's Trevi Fountain, complete with statues. In the same room two floors above, you'll find the ornate tile design of a Turkish bath.