From the volcano house we walk to the world's largest lava bomb on the outskirts of Strohn. You will be surprised how it was formed! This is where "Strohn Switzerland" begins, where the volcanoes erupted. We walk past an imposing lava wall down to the Alf and along a mighty basalt stream to the Sprinker Maar. The way back is uphill, but it's worth it because you can take a look at the Wartgesberg lava pit from above.