Ice climbing is possible once the waterfalls in the Paznaun valley are completely frozen, usually between January and March. Conditions always depend on temperatures and the weather. Minimum age requirements vary, so please check with your mountain guide or ski school in advance.
More important than age are a good basic level of fitness and sure-footedness. Experienced climbers who are confident using ice tools and crampons can explore the spectacular frozen landscape independently with the right equipment, for example at the Kappl icefall. If you are new to ice climbing, joining a guide or course is the safest and easiest way to get started.