Demjén Gyógyfürdő és Aqua-park

Demjén Gyógyfürdő és Aquapark lies in the Hegyeskő valley in the southern foothills of the Bükk, a short drive from Eger, and it is one of three bathing operations the Cascade complex runs on the same ground, alongside a large cave bath and a four-star spa hotel. The well behind all of them was sunk in 2006. The bath's own page puts the water at 690 metres depth and 68 °C where it surfaces, and the published analysis describes a sodium-calcium-hydrogencarbonate water, hard, fluoridic and sulphurous, with a notable iron and metasilicic acid content. The operator's list of uses covers rheumatic complaints, degenerative wear of the joints, osteoporosis, gout, bone injuries, preparation for and recovery after orthopaedic surgery, and stress, and it names infectious disease, malignancy, heart failure, circulatory disorders, thrombosis, blood disorders, asthma, hypertension and pregnancy as reasons not to take the cure.

The distinguishing feature is the timetable. The bath calls itself the bath of the four seasons and stays open every day of the year from 9 in the morning until 2 the following morning, with the pools cleared at 1:30; night bathing under the open sky, rather than any single attraction, is what it sells. Outdoors there are six medicinal pools at different temperatures plus a seasonal swimming pool. A covered indoor section adds two more medicinal pools, a Finnish sauna with its plunge basin, a steam cabin, a Kneipp pool and a salt cabin, but it opens only from Friday to Sunday, 9:00 to midnight, with the sauna and steam cabin running 10:00 to 22:00.

The aquapark holds a rubber-ring rafting slide and a kamikaze slide, a multi-lane racing slide, and a diving pool with three platform heights over water up to 4.5 m deep; children under 120 cm are barred from the main slides. It runs seasonally and only in good weather. A long massage menu is offered alongside, from medicinal and Swedish-technique massage through green tea, grapeseed, lavender, peppermint-rosemary, orange-cinnamon, coconut and salt treatments to a migraine therapy and a foot massage. Since February 2015 the adjoining Hotel Cascade Resort & Spa has held medical-hotel certification from the national public health authority.