The Cincinnati Maze (9T-maze) is an evolution of the Biel Maze with an increased number of interconnected T-mazes.
It is most commonly used as a water maze to avoid scent issues and is used on rats to study egocentric navigation (memory). In order to avoid any possibility of external cue use, the maze is constructed in IR-transparent Perspex to run the experiment in full darkness and ensure that movements are due to egocentric and not allocentric mechanisms.