Derkul
Native name	Деркул (Ukrainian)
Location
Country	Russia, Ukraine
Region	Rostov Oblast, Luhansk Oblast
Physical characteristics
Source
• location	Central Russian Upland
• coordinates	49°38′1″N 39°38′5″E / 49.63361°N 39.63472°E / 49.63361; 39.63472
Mouth
• location	Donets
• coordinates	48°35′12″N 39°41′26″E / 48.58667°N 39.69056°E / 48.58667; 39.69056
Length	163 km (101 mi)[1][2]
Basin size	5,180 km2 (2,000 sq mi)[1][2]
Basin features
Progression	Donets→ Don→ Sea of Azov

The Derkul is a left tributary of the Donets located in the Luhansk Oblast of northeast Ukraine, on the border to the Rostov Oblast of Russia.^[1] It is 163 kilometres (101 mi) long, and has a catchment area of 5,180 square kilometres (2,000 sq mi).^[2]

The Derkul rises north of Markivka in the Ukrainian Luhansk Oblast on the western foothills of the Central Russian Upland. It flows mainly in a southerly direction through a hilly plain in the northeast of the oblast and after 163 km flows on the left into the Siverskyi Donets. In parts of the lower course, it forms a border of the Rostov Oblast of Russia. The Derkul flows through the urban-type settlement of Bilovodsk at the lower reaches. The most important tributary of the Derkul is the Polnaya from the left.