Today I will show you how to make a fold-away bridge. It is a simple and fun way to undestand how redstone works and it is great for parkour, adventure maps, etc.

1. Clear 7 rows of space.

2. Place a sticky piston on one of the 2nd to outside rows. Remember that it has to face outwards.

3. Place a block of your choice in fron of every piston.

4. Place a 3 block high wall, 2 rows away from from the pistons.

5. Place a lever on the middle block of the wall.

6. Place a single block right behind the wall. Then leave one space in the row and place another one.

7. Place a repeater behind every piston. Make sure they face the piston.

8. Switch the lever on.

9. Carry redstone all the way down from the block you placed behind the lever. It should connect to the repeaters.

10. Everytime the redstone runs out of power, place a repeater there. The pistons the secondary repeaters are placed next to will not work.

11.  Place a block 2 rows away from the wall with the lever and in  the same colum as the missing block.

12. Place a sticky piston on top of it facing the redstone.

13. Place another 2 blocks behind it.

14. Carry the redstone from the ending point to the piston. The bridge should now come in and come out on its own.

15. You can edit its speed by right-clicking repeaters.

16. Cover it in.

17. Done!