屋根の上

on the roof

→ 屋根
phrase Uncommon #16,630
on the roof Literally means “on top of the roof.” The particle に can follow it when indicating location or destination.
JA: 屋根の上に猫がいます。
EN: There is a cat on the roof.

猫が屋根の上歩いてる

The cat is walking on the roof.

全部探した地下室屋根裏屋根の上どこにも居ねえ

I looked everywhere—the basement, the attic, even the roof—but they’re nowhere to be found.

— 荒野の用心棒 (1964)

屋根の上!

It's on the roof!

— もののけ姫 (1997)

見慣れない青い鳥が屋根の上にみえる

I can see an unfamiliar blue bird on the roof.

屋根の上見てごらん

Look at the cat on the roof.

屋根の上見てこい

Go check the roof.

— 炎628 (1985)

屋根の上何やってるんですか

What are you doing on the roof?