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Deltapark is an easy place to give the sightseeing schedule a rest. Its lake setting is part of the appeal, alongside pools, sauna areas and quiet places to sit. You can visit while staying elsewhere, but non-resident access is by advance reservation and subject to space.
Choose the session before planning the rest of the day. Check which facilities, towels or meals are included, since a morning visit and a longer package may offer different things. Ask specifically before bringing children: an exception described for hotel guests should not be assumed to apply to day visitors. Sauna clothing rules also vary between areas.