Four individuals are observed walking eastward through a concrete underpass structure in Mramor, Bulgaria

Four individuals are observed walking eastward through a concrete underpass structure in Mramor, Bulgaria. The underpass features raw concrete walls and ceiling, with a metal guardrail system visible on the structure's upper surface. The ground within the underpass is covered with light brown and grey gravel mixed with patches of darker soil. The individual closest to the camera is seen from behind, wearing a dark red hooded puffer jacket with the grey hood up, blue denim jeans, black gloves, and blue athletic shoes with white soles. A blue and orange patterned backpack is worn, and a small black bag hangs from the left hip. Ahead of this individual, three others are also walking away from the camera towards the underpass exit. The second person from the front wears a dark blue jacket and backpack. The third person wears a camouflage-patterned jacket and a light-colored backpack. The fourth person, furthest ahead and near the exit, wears a dark jacket and a dark backpack. Beyond the underpass exit, an open field or agricultural land extends under a cloudy sky, with a distant mountain range visible on the horizon. The interior of the underpass is dimly lit, contrasting with the brighter exterior light. Rectangular lighter patches are present on the right concrete wall, and a vertical greenish stain runs down the left concrete wall near the entrance.