The Nagyerdő is Debrecen's green backyard — a 2,000-hectare oak forest on the northern edge of the city that functions as park, spa complex, university campus, and zoo all at once. Tram line 1 runs in a loop from the city centre out to the forest and back, and locals treat the ride as a Sunday outing. Once there, the choice is yours: thermal baths, paddleboats on the artificial lake, the small zoo, the amusement park, or just a walk under the oaks.
The Aquaticum complex is the main thermal-bath draw — indoor and outdoor pools fed by 64°C medicinal water from 1,000 metres down. The Mediterranean-styled indoor pool with its waterfalls and palms is open year-round; the outdoor strand opens in summer.