Excerpts from Books and Wikipedia
"Lithuania is the southernmost Baltic state, with a population of 2.9 million and a residual Russian minority of only about 6 percent. But relations with this gigantic neighbor are tense—despite a continuing dependence on Russia as a trading partner. One reason for this strained relationship has to do with neighboring Kaliningrad, Russia’s exclave facing the Baltic Sea (Fig. 4-21). When Kaliningrad became a Russian territory after World War II (Russia still regards this exclave as an important outpost), Lithuania was left with only about 80 kilometers (50 mi) of Baltic coastline and a small port that was not even connected by rail to the interior capital of Vilnius. Significantly, Lithuania joined NATO in 2004, and a year later it called for the demilitarization of Kaliningrad as a matter of national security. Russia did not oblige. Following in the footsteps of Estonia and Latvia, Lithuania joined the Euro zone in 2015." [Geography: Realms, Regions, and Concepts, 17th Edition, p. 188]