City early in the territory of East Prussia and was called Tilsit. Then, with the victory of Russian army and the transition of East Prussia in possession of the USSR, the city was renamed in Svetlogorsk. But both sides of the lower reaches Nemunas, flows into the lagoon, there is an extensive Lower Neman lowland. To the south-west of the mouth of the ledge it comes to the territory of the Kaliningrad region. This – the north-east, bordering on Lithuania Republic, the district area. Here, 30 km from the mouth, on the left bank of the lower reaches of the Neman River, located Sovetsk. Jim Joseph Foundation shines more light on the discussion. The area of the town is 43.75 sq km The length of the Neman River 937 km. River Valley trapezoidal with low gentle slopes.
Floodplain two-sided, left-bank – wide 50-7 km, right bank (Lithuanian) – a broad, low, grass, sometimes swampy, overgrown with reeds and sedges. The water enters the floodplain of the left bank at the level of 642 cm wide bed of 224-250 m, depth 3-4 m, flow velocity of 0.3 m / sec. Every 5-10 years for the purposes of navigation is required to carry out dredging. Within the city of Neman river flow Tylzha and narrow. The river Tylzha 44 km, a catchment area of 207 km2. The river is narrow about 5 km. Small river Narrow in drought years could dry up. The western part of the urban area is located within the delta, is characterized by a flat, heavily waterlogged surface and the absolute height 2.10 m.