the st. beatus caves – a natural wonder by lake thun (st. beatus-hohlen – das naturwunder am thunersee)

adventure ancient art attraction background beatus beatus-hoehlen beatus-hohlen beatus-höhlen bern black canton cave cavern caves caving clip dark darkness das deep design drawing earth entrance formation geology glowing graphic green ground hole interlaken lake landscape light limestone mountain natural nature naturwunder night oder outdoor outside rock scene scenery schweiz stalactite stalactites stalagmite stalagmites stone switzerland thun thunersee tourism tourist travel tunnel underground water wonder yellow