The Neretva Delta is the largest and most significant agricultural area on the Croatian Adriatic coast, and one of the most ecologically valuable wetlands in the entire Mediterranean region. It covers approximately 12,000 hectares on the Croatian side and is recognized as a Ramsar Wetland of International Importance since 1992. Together with Hutovo Blato in Bosnia and Herzegovina, it forms a unique transboundary wetland of exceptional biodiversity.
The delta begins roughly 30 kilometres from the sea, where the river gradually spreads into a wide alluvial plain. Before human intervention, the Neretva had 12 distributary branches. Today only four remain, shaped by decades of hydraulic engineering and land reclamation.
The most significant transformation of the delta took place during the 1950s and 1960s. After World War II, large parts of the wetland were drained with technical and financial assistance — first from the Soviet Union, and later from the Food and Agriculture Organization (FAO). The primary goals were the eradication of malaria, which had plagued the region for centuries, and the creation of productive agricultural land for local farmers. Hundreds of kilometres of drainage channels — called jendeci — were dug, and the excavated soil was piled alongside to create small rectangular plots of land, most of them originally accessible only by boat. Between 1968 and 1972, two dams with floodgates and ship locks were built: one near Opuzen to control water inflow, and another at the delta mouth to prevent seawater intrusion. What was once a vast marsh with 12 river branches became a mosaic of cultivated fields, channels, and remnant wetlands. The first, smaller-scale melioration efforts actually date back to 1881, when the fringes of the marshland were first made usable for agriculture.
The fertile soil of the delta supports a remarkable variety of crops. The most iconic is the Neretva tangerine (neretvanska mandarina), which arrived in 1933 as a gift from the Japanese consul to the Kingdom of Yugoslavia. Strictly speaking it is a Satsuma (Citrus unshiu), seedless with a thin peel and exceptional flavour. Today, tangerine plantations cover the largest share of agricultural land in the delta — around 25% — and the Neretva is the only place in the world where mandarins are harvested by boat, navigating the labyrinth of channels between the orange-laden trees. Other important crops include watermelon, tomatoes, cucumbers, lettuce, nectarines, and plums. In recent decades, greenhouses for intensive vegetable growing have also become common.
Beyond the cultivated areas, the delta's remaining wetlands support rich natural vegetation: extensive reedbeds of common reed (Phragmites australis) and giant reed (Arundo donax), wet meadows, willow forests, and open water communities. The area hosts 618 vascular plant species in total.
Despite dramatic transformation, the Neretva Delta remains one of the most biodiverse areas in Croatia. At least 313 bird species have been recorded, making it a critical stopover on the Black Sea–Mediterranean migratory flyway. Notable species include the Eurasian spoonbill, pygmy cormorant, ferruginous duck, great bittern, and black-winged stilt. The delta also shelters 35 freshwater fish species, 18 of them endemic, as well as 11 amphibian and 23 reptile species.
Several settlements in and around the delta deserve their own pages. Metković is the main town of the lower Neretva valley, an important transport and commercial hub with a long history as a river port. Opuzen lies at the point where the river splits into its four remaining branches and is the centre of the tangerine-growing region. Vid, near Metković, stands on the site of ancient Narona, a major Greek and later Roman trading city established in the 4th century BC — today home to the Arheološki muzej Narona, the first museum in Croatia built directly over an archaeological site. Ploče is the main Adriatic port of the region, important for cargo traffic and ferry connections. The villages of Rogotin, Blace, Komin, and Desne are smaller settlements woven into the delta landscape. Further inland, Čapljina in Bosnia and Herzegovina is the gateway to Hutovo Blato.
The traditional boat of the Neretva, the lađa, remains a symbol of the region. Every year in August, the Maraton lađa — a 22.5 km rowing race from Metković to Ploče — draws over 400 participants and has become the largest maritime sporting event in this part of Europe.