The maze above has a number of plain cubes glued into fixed positions. The red cubes are free to roam. There is a single cube, a domino (two red cubes glued together), and a 2x2 block.

The objective is to maneuver the single cube from its start position in the front corner (shown) to end up over the finish space, marked F.

The catch:  the single cube must always remain in the third layer up, with two cubes stacked below it! The only way it can move is if there is a temporary "floor" moved next to it on the second layer, on which it can travel.

Thus your task is to move the domino and square block into the strategically correct positions to assist the cube in its move toward the goal.

Some more catches:  the domino must always be supported by one layer of cubes below it, although it can stand up tall or tip down flat on its level. When it's flat, it must be fully supported underneath. The square block must always be on the bottom level, although it can rest on its square face or stand on its side. This block is thus useful in providing either one or two layers of support.

Try even a few moves just in your head, and you will soon want this nicely made model to move by hand. It's handcrafted in wood, about 9" square, and makes a superb coffee-table toy. The grid pattern is laser-engraved.

Dr. Andy Liu, a professor at the University of Alberta in Edmonton, Canada, has found a 247-move solution. Can you beat that?

For more information about this puzzle and the development of rolling-block mazes, see Bob Abbott's great website, Logic Mazes. He also provides links for playing rolling-block mazes online.

To get your own hands-on copy of the Rolling-Block Maze by Erich Friedman, for ages 10 to adult, order here.     $75