Quick FactsOverview
About Y-40 The Deep Joy
Y-40 The Deep Joy, Italy is a 42.15 metre deep thermal diving pool at the Hotel Terme Millepini in Montegrotto Terme, in the Euganean Thermal Basin of the Padua province in Veneto, approximately 12 kilometres southwest of Padua city. The pool holds 4,300 cubic metres of thermal water maintained at 32 to 34 degrees Celsius, drawn from the same salt-bromine-iodine source that emerges elsewhere in the basin at 87 degrees Celsius and is cooled before use. The pool features a funnel descending from 1.3 metres to 40 metres, platforms at depths of 1.3, 6, 10, and 12 metres, underwater caves, and a suspended transparent tunnel that lets non-divers walk beneath the water. Padua, home to one of Italy oldest universities, is the nearest major city.
These terme are famous for a Guinness World Record. When Y-40 opened on 5 June 2014, designed by architect Emanuele Boaretto with depth measured by Italian freediver Umberto Pelizzari, it was recognised as the world deepest swimming pool for diving, replacing Belgium Nemo 33. It held the record until 2020, when the Deepspot pool in Poland and later Deep Dive Dubai surpassed it. Today it is the third deepest in the world and deepest in Europe. The pool is housed at the four-star Hotel Terme Millepini.
Y-40 is a distinctive hot spring resort Italy maintains in the Euganean thermal corridor.
Location & Access
Getting to Y-40 The Deep Joy
Y-40 The Deep Joy is reached by a short drive to Via Cataio 42 at the Hotel Terme Millepini in Montegrotto Terme, directly accessible from the A13 motorway and the Padua regional road network, approximately 12 kilometres southwest of Padua city centre. The hotel is drive-up accessible with on-site parking, and the Y-40 pool, hotel wellness areas, and other facilities are connected on paved paths through the grounds.
From Venice, the drive takes approximately 50 minutes west via the A4 and A13 motorways. From Verona, the drive is approximately 1 hour east via the A4. From Bologna, the drive is approximately 1 hour north via the A13. From Milan, the drive is approximately 2 hours 30 minutes east via the A4 and A13. Montegrotto Terme has its own railway station on the Padua to Bologna line, making this one of the easier hot springs near Padua to reach by train, with the Y-40 pool a short taxi ride from the station.
Euganean Thermal Basin
Montegrotto Terme sits in the Euganean Thermal Basin, which also includes the larger spa town of Abano Terme, with dozens of thermal hotels drawing from the same geothermal source. The adjacent Colli Euganei Regional Park preserves volcanic hills, Benedictine abbeys, medieval villages, and vineyards. Combining a Y-40 diving session with Padua art history (Scrovegni Chapel, Saint Anthony Basilica) and a Venice day trip makes a strong northern Italy wellness and adventure itinerary.
Suitability & Accessibility
Who Should Visit Y-40 The Deep Joy
Y-40 The Deep Joy suits scuba divers, freedivers, apnea trainers, dive course students, and curious non-diving visitors who want to see the pool from the suspended transparent tunnel without entering the water. The warm 32 to 34 degree Celsius thermal water allows extended diving sessions without a thick wetsuit, and the controlled pool environment with platforms at 1.3, 6, 10, 12, and 40 metres makes the site especially suited to training, certification courses, equipment testing, and underwater photography.
These acque termali also support hotel wellness bathing in the Hotel Terme Millepini thermal pools for guests who are not diving, giving the complex both a classical Euganean thermal programme and a signature deep diving experience in one property. This hot spring resort Italy preserves is the only facility of its kind in Europe, drawing divers from across the continent for both record-depth training and leisurely thermal immersion between dives.
Accessibility at Y-40 The Deep Joy
The modern Hotel Terme Millepini reports accessible facilities for guests with reduced mobility, including hotel wellness areas. The transparent underwater tunnel allows non-divers and visitors with limited mobility to see the deep pool from inside without entering the water. Those seeking a classical Euganean thermal resort experience without the deep diving focus should consider Terme Preistoriche Resort and Spa, a short drive away in the same Montegrotto Terme area.
Safety & Etiquette
Y-40 The Deep Joy Safety Tips
Y-40 The Deep Joy is generally safe as a professionally staffed and highly structured diving facility with instructors, lifeguards, and dive supervisors on duty, but divers must respect the specific depth, certification, and session rules that govern diving to 40 metres in a confined thermal pool. All diving sessions require pre-booking and either proof of scuba or freediving certification or participation in a certified course. Non-divers may still access the facility via the transparent underwater tunnel, which has its own safety rules.
Dive medical consultations and signed liability forms are standard. Divers with cardio-vascular, respiratory, or pressure-sensitive medical conditions should discuss their plans with the dive medical team before booking. The 32 to 34 degree Celsius thermal water is warm but extended deep dives still carry hypothermia and decompression risks that must be managed by the dive plan.
Rules and Etiquette
Shower before entering the pool, following the resort rules. Do not use soap, shampoo, or detergents in the thermal water. All equipment must be approved by the Y-40 staff and standard dive briefings are mandatory before each session. The underwater caves and tunnel features are controlled environments; respect the dive supervisor instructions at all times. The bromine-iodine content can stain light-coloured swimwear and silver jewellery.
Climate and Travel Notes
Veneto has a humid subtropical climate with hot humid summers and cold wet winters. Because the pool is indoors and climate controlled, the Y-40 experience is reliable year-round regardless of weather. Confirm current session hours, course availability, and non-diver visit times on the official Y-40 website or by phone before travelling.
