At the end of the 18th c., when Kaunas became the border post of Russia, the Tsar decided to transform the city into a fortress, but the idea materialized only in 1871. Germany finally became united, and there was a need to strengthen the empire’s western borders. In 1880, Tsar Alexander II ratified the Kaunas fortress plan, covering a 15 sq. km area. The work started in 1882-1889, but construction continued until 1915. Stages of construction  Construction was carried out in several stages. First, a defense circle consisting of 7 forts and nine batteries, and central fortifications was built. Construction of administrative buildings in the city center, reconstruction, and refinement…