The Long Hall is the entrance to Wonderland. It is located down the Rabbit Hole. There are lots of doors around the hall,but they are locked. The only unlocked exit is too small to walk through. In the 1949 movie, the doors open then close...then the number of doors decrease! Alice runs for a door which shrinks and a table with a key on top appears out of nowhere....
It is rectangular in the book, but round in the 2010 film.
These doors,as shown in 2010 are used as spyholes, which might explain why they are locked