Little sparks a child's imagination like the thought of living as a king, queen, knight or beautiful princess inside a castle. Castles line the German rivers and lowlands, dot Austrian hills and perch perilously in Swiss mountains. Walt Disney recognized and further immortalized them as a symbol of enchantment.

But where yesteryear's castles were built over decades (or even centuries), today's are inflated - and then deflated again - in a matter of minutes. A Hüpfburg, literally "hop castle," is a delightful and colorful contraption for bouncy children. They can often be found at fairs, and can even be rented for private birthday parties.

No, a Hüpfburg isn't a real castle, but that also means no sharp arrows or boiling pitch. Just a few elbows and happily tired legs.