Learn Hardcore Japanese: yama no ue ni yuki ga arimasu. - There is snow on top of the mountain.

In Japanese, の is a genitive or possessive particle that links two nouns. Here 山の上 literally means “the top of the mountain.” The first noun (山) modifies the second noun (上), so you put の in between.

Why can’t we say 上の山 to mean “the top of the mountain”?

Word order matters: XのY means “Y of X.” If you said 上の山, it would mean “the mountain belonging to the top,” which doesn’t make sense. You must put the thing being possessed first (山), then の, then the thing possessed (上).

What does the particle に do in 上に?

に marks a point in space or time. In an existence sentence like 雪が上にあります, に indicates the location where something exists (“at the top”). Without に, the verb あります (to exist) would have no specified location.

Why is が used before あります instead of は?

が marks the subject of a sentence when you’re stating that something exists (or new information). 雪が上にあります highlights “snow” as the thing that exists up there. If you used は (雪は上にあります), you’d be topicalizing “snow” and implying a contrast or already‐known topic, e.g. “As for snow, it exists up there (but not elsewhere).”

What’s the difference between あります and います?

Both mean “there is/are,” but:

あります is used for inanimate objects or things without will (snow, mountains, books).
います is for animate beings (people, animals).

Why is there no です at the end of the sentence?

あります itself is a polite verb form (“to exist”). You don’t add です after it. You only use です after nouns or な‐adjectives when making a polite copular statement (e.g. きれいです).

Could you say 山の上に雪がある instead?

Yes. ある is the plain (dictionary) form of あります. You’d use ある in casual or written contexts (e.g. diaries, novels). あります is the polite form you’d use when speaking politely.

Do we always need to mark location with に when using あります/います?

Almost always, yes. If you omit に, the sentence loses its clear location. In casual speech, you might drop particles, but generally “exists at/in…” requires に.

Can 上 ever mean something besides “top”?

Yes. 上 can mean “above,” “on,” or “over.” Context and attached particles clarify:

机の上 = on top of the desk
空の上 = above the sky (in the sky)
But here, 山の上 specifically means “the summit.”