Veľký Lél island is a mosaic of forest, wetland and meadow biotopes combined with regenerative management. The area of the island is 250 ha. It is an example of sustainable landscape management using traditional practices without overexploitation of nature and living in accordance with other species.
It has been under care of BROZ since 2006. Since 2013 various measures have been taken to improve the state of the island. A small scale farm was built in the vicinity and extensive grazing reintroduced to the island. The animals (cattle, sheeps, horses and goats) help to create different habitats and maintain biodiversity there. Selected parts of the island are available to the public and used for recreation and raising awareness of the necessity to protect the biotopes and manage them sustainably. The island offers a peaceful place for relaxing. There are nature educational trails on the island, it is possible to rent a canoe and sail around the island to enjoy the nature with robust old oaks, poplars and pollarded willows. A small regulated camping site and four small cabins are available to support ecotourism in the region. The facilities are also helping with employment in the area where joblessness is high.

However, due to numerous changes in the Danube basin in the past, the environment of the island has become dry. And the key for the healthy state of the biotopes is a sufficient amount of water. That is why BROZ reopened two inlets that are now bringing water to the island. Anyhow in the past there were three main inlets. The last left to be open. The restoration of the third outlet would create a remote space for bird nesting without man interruption, bring the water back to the island, especially during the hot summer months and because of flow improvement prevent sedimentation.