It seems that the entrance to the MI6 Underground Station has been revealed. Earlier today, thanks to our source Mr Potato Head, we learnt that Bond Mild Spoiler Warning (Highlight To Read) would be seen entering the station from a public landmark. However, Mr Potato Head was vague as to what this landmark actually was.
I did some research into the area of the Piccadilly Line and the abandoned Down Street Station and I came up with three possible landmarks which are in the close vicinity; Wellington Arch, Apsley House and St. James' Palace.
The Wellington Arch
Taking an educated guess I'm going to theorise that the Wellington Arch is our landmark, this is most notably because it is the closest of the three to Down Street as this map shows.
The Wellington Arch and Down Street highlighted in Blue
Located at Hyde Park Corner, Wellington Arch (known also as Constitution Arch or Green Park Arch), was built in 1826 as the entrance to Buckingham Palace. A statue of the Duke of Wellington was located on top of the arch until 1882 when it was relocated to Aldershot. In 1912 a statue by Captain Adrian Jones, known as 'Peace Descending on the Quadriga of War', was placed on the top. The arch was opened to the public in 2001 having undergone restoration work by the English Heritage.
So if the Wellington Arch is the mentioned public landmark, then how exactly is it a homage to a past Bond film? Well let me begin by saying that it is a homage to the first Bond film, Dr No. If you watch the scenes in Dr No's lair you'll notice a very large painting on one of his walls. This painting is actually a reproduction of the original painting, as the original was actually stolen in 1960 and to this day has never been recovered! According to Bond-lore Dr No was responsible for the theft! But that still doesn't explain the homage does it? Well yes, it does. The painting is actually of the Duke Of Wellington, who the Wellington Arch is named after!