1435 mm gauge railway system infrastructure has been started to be developed in Lithuania in 2010 in the scope of the project “Rail Baltica”. The first section was constructed in 2015 according to standard technical parameters for the 120 km/h design speed; the second section requirements included requirements to provide the possibility to transport civil and military freight by 1435 mm gauge railway to Kaunas from European countries. Additionally, during the second stage of the development of 1435 mm gauge railway development, new standard technical parameters for 249 km/h design speed were assigned. Setting different requirements for each stage raises the discussions about why railway lines are not designed with maximum horizontal and vertical curves radii, allowing the shortest routes, at least 249 km/h passenger traffic speed, 120 km/h freight traffic speed and minimal carriage time, respectively. An article analyses the impact of the urbanized areas, as well as nature and heritage constraints, on the standard technical parameters for the development of the 1435 mm gauge railway infrastructure. This article attempts to answer the main question: why are the railway lines not planned as completely straight lines at once, allowing for the construction of the shortest possible rail-way routes, maximum traffic speeds and the shortest passenger and freight carriage times.