On the AI Attic, this directory contains only a single file: adventure-11.hqx
That file, when decoded with BinHex 4.0, gives this file: Adventure_1.1.cpt
That file, when decompressed with Compact Pro (or an equivalent, such as macunpack),
gives the contents of the "Adventure" subdirectory. 

The result is a copy of Ken Wellsch's port of David Platt's 550-pointer.
Its taxonomical name is ARD_0550.