Around Fort IV of the Osowiec Fortress

Park in the car park at the visitor centre, on the edge of Carska Droga.

Yellow signposting ‘Wokół Fortu IV twierdzy Osowiec’, directional arrows

(S/E) From the car park, cross Carska Droga with care and continue straight ahead onto the forest path that leads into the pine forest until you reach a junction.

(1) Turn left and, further on, pass the first path on the right.

(2) Turn right at^{the second} path to climb up to the ruins of the barracks. Continue along the short circular path until you rejoin the signposted path and follow it to the right. At the T-junction, turn left, cross the wooden footbridge which branches off the circular path towards the moat and reach the viewing platform.

(3) Turn round, return to the path and carry on straight ahead.

(4) At the ruins of the powder magazine, carry on straight ahead. At the junction, turn right, then immediately right again. Further on, at the three-way junction, continue along the path on the right.

(5) At marker post no. 14, turn left onto the small, inconspicuous path leading to the final ruin, a small blockhouse hidden beneath the pine trees. Return to the marker post and take the path to the left. At the junction, turn right and rejoin the route you took earlier.

(1) Carry on straight ahead and, following the route back in the opposite direction to the way out, return to the car park (S/E).

Access is by road, via Carska Droga, approximately 4 km from the DK65 national road, near Osowiec-Twierdza.

An entry pass for Biebrza National Park (karta wstępu) is compulsory to use the trail and must be carried at all times. It costs 10 zł (~€2.30) for a full-price ticket and 5 zł (~€1.15) for a reduced-price ticket, per day. It can be purchased online (biebrza.eparki.pl) or at the park’s headquarters at Osowiec-Twierdza 8. Access is permitted only during daylight hours, from one hour before sunrise to one hour after sunset.

The ruins are dangerous. Some are cordoned off with barriers and off-limits. Do not enter or climb the structures, and stay on the marked path.

The footbridge decking may be slippery in wet or icy conditions. Sturdy footwear is recommended. In winter, the path may be covered in snow or ice. Check conditions before setting off out of season.

A covered shelter with benches and stretching stations are dotted along this trail, which is designed as a running route. Bring water with you; there are no refreshment points along the route.

Osowiec Fortress was built by the Russian army between 1882 and 1892, and subsequently modernised up until the First World War. It blocked the passage across the Biebrza River, controlling the strategic railway line from Białystok to Ełk (via Grajewo) and the only passable crossing point through the marshes on the western frontier of the Russian Empire.

In 1915, the garrison withstood a prolonged German siege. On 6 August, following a chlorine gas attack, the unprotected Russian survivors launched a counter-attack and repelled the assault: the episode has gone down in history as the ‘Attack of the Dead’ (Atak umarłych). Faced with the threat of encirclement, the Russians dynamited much of the fortifications before withdrawing on 18 August 1915, hence its current state of ruin.

(4) Fort IV ‘Nowy’ is the most recent of the four forts in the complex. Built around 1891 under the supervision of engineer Nestor Bujnicki, it is considered to be the first fort in the Russian Empire to be cast entirely in concrete. Scattered throughout the pine forest, one can see the ruins of the barracks (2), the vaulted powder magazine (4) – the best-preserved section – small blockhouses and observation posts (5), earthen ramparts and a moat filled with water, overlooked by a platform (3).

Rare flora, reminiscent of that found in the mountains, grows on the weathered concrete of the ruins: the lime washed away by the rain creates a limestone substrate, and limestone concretions form inside the structures, as in a cave.