activity adventure exploration exploring forest people astronomy cherenkov explore gammarays mirror mirrors science technology telescope Alcudia Alcúdia Balearic Islands blue boys break child children coastline danger explorers island majorca Mallorca natural nature rocks rocky sea shore Spain Teenagers tide water waves canoe cave cliff coast dark entrance rock Sardinia clouds sky Monaco Monte Carlo museum oceanographic oceanography research submarine submerged yellow follow future hike hiking journey lead path road trail tree Trek unknown walk walkway boy cove fun harbour kid mediterranean slipway spanish stone wave wet bank cloud cold destination direction drifts exercise extreme foolhardiness freezing high icy landscape mountains norway norwegian plateau snow tourism tourists travel white beach careful Catalan catalonia Catalunya cautious check conifers edge green pines shade summer sunlight test trees Bengal Cats bmw cabrio car convertible M3