A military bunker located near the coordinates 52.8490692, 15.9316383 in Poland. The provided web search results do not offer any information about this specific bunker. However, the name 'Schron bojowy dla km. Regelbau B1-1' suggests it might be related to Regelbau bunker designs, which were a series of standard bunker designs used by Germany during World War II.
The Regelbau B1-1 specifically could imply a type of small infantry bunker or machine gun emplacement. Without further information, the historical context, architectural features, and current state of this bunker remain unclear.