On the Nunhead-Crystal Palace branch of the London Chatham & Dover Railway Opened: 1865, Closed: 1954
This is the South portal which is adjacent to the site of the old Crystal Palace High Level station, see this link
The area that used to be the old Crystal Palace High Level station is now a housing development.
The tunnel was named after Sir Joseph Paxton, who designed the original Crystal Palace, a huge iron and glass greenhouse-like construction that was erected in Hyde Park (central London) to house the Great Exhibition of 1851. The building was transferred to Sydenham in South-East London after the exhibition, and gave its name to the area (and nearby football team) now known as "Crystal Palace" It was destroyed by fire 30 November 1936.
There's a good picture of the crystal palace here , and an interesting Wikipedia entry.
The other end (North Portal) is at the end of "The Gradient" SE26 approx N51 25.65 W0 04.32.
Parking is available right by the South Portal, but as this is a residential area it may well be residents only.
A couple of other links: