We just made 80 of these skyline centerpieces.
They had 4 sides but no bottom.
They had a light inside to make them glow at the party.
You could use battery closet lights...or I used puck lights from
Costco that were nice and bright led lights. A few battery operated candles also would work.
They were easy to make and easy to connect together but 80 of them sure took a whole bunch of time to cut out!