Lentvaris ( pronunciation (help·info), Polish: Landwarów) is a city in eastern Lithuania, 9 km east form Trakai, an important center of transportation, because many roads and railroads cross here. Lake Lentvaris is located near the city.

In the 18th Century, the town of Lentvaris, laid within the Polish–Lithuanian Commonwealth, . It was owned by the Lithuanian noble Sapieha family; and later by the Tyszkiewicz family (since 1850). Following the partitions of Polish-Lithuanian Commonwealth the town became a part of the Russian Empire. In the 19th century the Tyszkiewicz family had a Tudor-style palace built (in 1885), and founded a park, designed by Édouard André. In 1869 a nail factory was established.

In the interwar period Lentvaris was held by Poland (since 1922). It was located within the Wilno Voivodeship, in the Wilno–Troki District of the Second Polish Republic. In September 1939, Nazi Germany attacked Poland in unison with the Soviet Union. The town was taken over on September 19, 1939. Polish soldiers, who fought in the September Campaign, were interned in the neighboring town of Kretinga by the Lithuanians. Between 1942 and 1943 a Jewish partisan unit headed by Abba Kovner operated in the vicinity and blew up a train near the Lentvaris station on the railroad from Vilnius to Grodno. Twenty one cars carrying troops and supplies were derailed. The train had been on its way from Warsaw to Vilnius.