The largest of them is the depot in Olsztyn, which handles passenger trains on the segments: Olsztyn - Korsze - Elk, Olsztyn - Mikolajki - Elk, Olsztyn - Szczytno and Olsztyn - Braniewo. In freight service, besides providing SM42 power for local freights, Olsztyn's ST43s, SU45s and SU46s are used to lead freight trains on the Olsztyn - Korsze - Elk line as well as to the border crossing at Skandawa/Zeleznodaroznyj.
 

The line from Chryplin to Woronienka to the Hungarian border was built in 1895 by the C.K. Austro-Hungarian State Railway, kkStB. The line was assigned to the Lvov region (ED Lemberg) of the kkStB railway, and from 1906 was merged into the newly-created Stanislaw Region (ED Stanislau). After the First World War in 1919 the line passed to the Stanislaw Region of the PKP. After the Second World War, the Soviets included the line in the Lvov Railways, and in 1992 the line became part of the newly-created Ukrainian Railways. The line from Chryplin to Woronienka is single-track and has the character of a mountain line, with steep grades and tight-radius curves. It runs through beautiful mountain past numerous and magnificent stone bridges and viaducts. It was recognized before the war in Poland as more picturesque than the famous "Zakopiank" (Chabowka - Zakopane).
 

The class 270 steam locomotive (PKP class Tr12) came into existence as an as a superheated steam variant of the 170 class (Tr11). Factories in the Austro-Hungarian empire began their production in 1917, and continued until 1925. In the inter-war period, Poland purchased 84 such locomotives from Austria, and the newly-established Warsaw Steam Locomotive Construction Company built 58 further examples. Together, 142 class Tr12 locomotives saw use. After the Second World War, 39 Tr12 locomotives saw use on PKP. They were employed in the Warsaw, Krakow and Gdansk regions. The Tr12 class was retired from service by 1969. In preservation, working Tr12-25 is stationed at the railway museum in Chabowka.