The last stretch of the Danube river – the Lower Danube – extends 1,000 km across Bulgaria, Romania, Moldova and Ukraine before it flows into the Black Sea. Numerous islands dot the river along this section. Decades of human modification of the natural landscape have left the islands, the river and its banks degraded. These modifications have included conversion to agriculture, hybrid poplar mono-culture plantations, introduction of non-native invasive species, infrastructure such as dykes, and pollution. Riparian forests, along the banks of the Danube and floodplain forests are important habitats for birds, fish and other wildlife, protect the riverbanks from erosion and act as a filter for water quality. Furthermore, natural floodplain and riparian forests protect coastal settlements from natural disasters, most notably from flooding. In 2000, a joint declaration was signed by the Environment Ministers of Bulgaria, Romania, Ukraine and Moldova to establish a Lower Danube Green Corridor. It provided the backbone for restoration activities to take place in the wider Lower Danube corridor or landscape. Over the course of the following two decades, a series of projects have been implemented within this overarching framework, many of which have tackled alignment with EU legislation such as the 1992 Habitats Directive. This report highlights lessons learnt from WWF's engagement in the region. Restoration efforts have involved policy work, training workshops, but also active removal of dykes and sources of degradation, and trials on relatively small plots to determine best methods for the restoration of forest dynamics. Activities have included numerous field-based interventions, site preparation, removal of invasive species and both passive and active restoration, even though it did not necessitate the plantation of a large number of trees. Economic studies have demonstrated that the benefits of restoration, in terms of ecosystem goods and services secured, and disaster mitigation, far outweigh the costs.