Marble Night City is based on great human engineering. This marble run product combines the beauty of science and machines, involving so many small gadgets. It is a self-assembly 3D wooden puzzle with Tower Distributors track race balls. Build the set and crank the handle. Watch marbles run crazy down the slopes and twisting turns. Breakthrough material restrictions and incorporate high-transparent acrylic. With a funnel-shaped track, the total length is extended to 2.5 meters. Rotate the handle, the steel ball will reciprocate along the track to experience the creativity of precision machinery with this wooden marble run puzzle. TOUGH FORTRESS: LGA01 Marble Night City is a handcrafted marble set with striking fortress. Build it with 294 building pieces and 10 marbles. MANY GEAR GADGETS: Consists of a tower distributor, spiral slopes, a crane lifer, a wheel lifter, a short slide and small switches. Intricate system of cogs, gears and wheels, full of crazy twists and turns. STEM CONCEPTS: Learn principles of Science,Technology, Engineering and Mathematics(STEM) HOBBY and GIFT: Precise laser cutting ensure you a fluent building experience. Also a great Christmas and Birthday gift for family and friends.