Yesterday, to round up the birthday festivities, we went to the Wenigzell Barefoot Park, a semi-short trail of about 1km, but you need about half an hour to do it, as you walk barefoot on all kinds of different surfaces. Some stations require balancing. Some feel very nice, others are more challenging (i.e. walking upstream in ice cold water, knee deep [for Julius] in mud).
All over a fun and totally free experience!