In Polish, it is known as Międzyrzecki Rejon Umocniony, in short MRU. You can recognize it under the English name Fortified Front Oder-Warthe-Bogen and German The Festungsfront Oder-Warthe-Bogen. It was a fortified military defense line of Nazi Germany. Now it is one of the fascinating museums of Poland. It is located between the Oder and Warta rivers, near Międzyrzecz and was supposed to protect the most vital section of the eastern border of Germany.It stretches close to 80km between Gorzow Wielkopolski and Zielona Gora. The history of this place begun in 1934 when Germans started to build there the most technologically advanced fortification system of Nazi Germany.
Although the history of this place lasts for almost one hundred years, the area where MRU is located is so huge that it still consists many mysteries. The plans of MRU are well known, but historians, archaeologists and passionate people who are interested in this place, state that there is still a lot to uncover.
From ww2 Germans, to Soviets and today to Poles
The area of Międzyrzecz became a stage t the spectacle f constructing an incredible project of fortification system. The first projects were created in 1932, designed by the special team of architects and specialists in constructing the military fortifications. Although Germans started construction on MRU in 1934, according to the plan it was about to be finished in 1951. The first stake of works included constructing of water obstacles and 12 light bunkers. In 1935 MRU was visited by Adolf Hitler. The major part of the fortification system was accomplished until 1944. In January 1945 the Soviet army reached the defense line in the course of the Vistula–Oder Offensive, it took them three days to break the German line. After the Worl War II Germans lost possibilities of accomplishing their plans.
MRU consists of 100 concrete defense structures partially interconnected by a network of underground tunnels. Each tunnel brings more interesting stories and seems to be a paradisial landscape to every passionate explorer of military constructions. One of the most interesting parts of complexes located in Gmina Międzyrzecz, in Pniewo. The central section of the bunches is interconnected with an underground system of tunnels. The corridors are 32 kilometers long and up to 40 meters deep under the ground. The system located underground consists elements like workshops, engine rooms, railway stations and barracks.
Another interesting part is located in the southern part of MRU. It is so called Borszyn Loop located near the village of Borszyn. It extends about 12 km to the north and stays one of the areas of explorations. In Borszyn you will find the most popular place where you can enter the labyrinth of MRU.
The bastion of bats
Nowadays, MRU is a very important place on the map of crucial places protecting the bat population. In the monumental tunnels of the old fortification live thousands of bats. Some of them belong to the rare species so every year dozens of specialists arrive at MRU in order to take care of them, counting their population or protecting them. According to the researchers, MRU is a shelter to over 35.000 bats of at least 12 species including the Daubenton’s bat, the Barbastelle, the greater mouse-eared bat, the long-eared bat (brown) and the Natterer’s bat
MRU became a friendly shelter to animals and people. This old fortified line holds thousands of secrets that await for the one who is ready to recover them. Step by step the group of passionate people who are ready to explore every corner of MRU discovers the most fascinating stories about this place. Due to their work MRU consists a small museum that helps to understand the history of this place.