Many of the scenes in this movie were directly copied from the illustrations of Sir John Tenniel, the original "Alice's Adventures in Wonderland" artist.
The scene where Alice finds herself growing bigger as she walks down a corridor was shot on a corridor that was constructed to get smaller, which reinforced the illusion on-camera.
Martin Short's head was digitally enlarged to three times its normal size, so to better replicate the Mad Hatter in Sir John Tenniel's illustrations.
Alice offers up "lions and unicorns" as a possible password for Wonderland. "The Lion and the Unicorn" was a rhyme that appeared in "Through the Looking-Glass". Lion is the totem animal of England, unicorn is that of Scotland.
This is, chronologically speaking, the twelfth adaptation of Lewis Carroll's famous novel "Alice's Adventures in Wonderland".