Located in Scotland, the Falkirk Wheel is the world's first and only rotating boat wheel. Its primary use is to connect the Forth and Clyde Canal with the Union Canal. With a diameter of 35-meters, it boasts two axe-shaped arms and water-filled caissons boasting an 80,000-gallon capacity, capable of lifting 600-tons (combined). The Falkirk Wheel is surprisingly efficient, needing just 22.5kW to run the electric motors. At $34.8-million, however, this work of art didn't come cheap. Videos after the break. Click here for first picture in gallery.