Nautilus, Escola do Mar is a diving and recreational boating school founded in the late 1980s, based at Porto de Abrigo in Sesimbra with an administrative office in Corroios, south of Lisbon. It describes itself as Portugal's first international dive school and its first professional dive center, and has long been a pioneer for PADI training in the country, running a 5-star PADI Instructor Development Center. Over more than 40 years it has trained thousands of divers, from first pool try-dives (Discover Scuba Diving) and scuba review refreshers through the full recreational course ladder to specialty and professional instructor levels. Alongside dive training it runs snorkelling trips, guided boat dive outings, and DGRM-accredited recreational skipper (nautical) courses, plus dive equipment servicing, dive insurance and logistics support for its students.