(top) Station Interior / public domain
(right) Location of the station and route heading north
Crystal Palace High Level Station was one of two stations built to ferry passengers to the 1851 exhibition hall and was the terminus of one end of the now defunct Crystal Palace and South London Junction Railway. The destruction of the Crystal Palace in a fire in 1936 led to a significant drop in passenger numbers, ultimately leading to it's closure in 1954.
An ornate pedestrian subway leads from what would be the high level station to what was once the the Crystal Palace, this survived the 1936 fire and the war and exists today as a grade II listed structure albeit in somewhat poor condition.
(right) High Level Station exterior / The Illustrated London News
(bottom) The park-side courtyard of the subway
Some of the stairwells are shown below, securely gated off.
Above is the station-side entrance to the subway, with stairs leading up onto the road. On the right is an undated picture from The Norwood Society showing some junior explorers having a go at the subway which was bricked up at that point.
Following where the tracks would have once led, the retaining wall remains in good condition and leads up a road to a private housing estate, the entrance to the Paxton Tunnel can be found at the end and is locked up tight. The other end is bricked up and it's sister tunnel further on is mostly the same.