The Metal Junk Arches is a monument that you can build on your planet entirely out of waste. Once built it provides huge amounts of happiness through tourism.

Requires level 25 university.  

Does not use a plot. You are only allowed 1 of these buildings per planet. 

If you demolish one, you do not regain any waste.

As with all Junk happiness buildings, it cannot be upgraded except through the use of halls and won't use up any waste in the upgrade.