Castle Run - Mini modular marble run

Here is a fun, creative activity. Build your own castle themed mini marble run. The blocks are easy to print.

Magnets can, optionally, be added to the flags. By doing this, you will have a nice grabbing tool for the steel balls too. While holding the ball with the flag, you can start the race in a tower entrance by putting the ball int the hole and dragging the flag downwards.

The blocks work beautifully on their own, but if you want to expand the creativity, they are also Lego compatible. The blocks are engineered to be great for 3d printing and assembly.

The download includes both a base set, on one plate, and all the individual pieces. I suggest you start by printing a single piece to ensure you are dialed in for the print.

Included in the package are more than 14+ different parts with intricate details. 

You may want to print with supports for better bed adhesion!

Extra materials:

• 4.5-5mm steel balls

• 5x1-2mm magnets (Optional)

Please share images of the great and inspiring castles you build. 

Update May 20th 2026: Re-added the 5x5 base plate. 

Have fun!