Usage of の vs を for the direction of a place

Question

I learnt that in Japanese, the の preposition is used to describe the direction of a place (up, down, right, left, next to, etc. For example:

• 部屋の中 (heya no naka): Inside the room.

• テーブルの上 (te-buru no ue): On the table.

But then I listened to a conversation that contains a sentence which I believe is written like this:

• あの 信号 をひだりへ 曲がってください (ano shingou o hidari e magatte kudasai): Please turn at that signal

In this case を is being used instead of の.

Is it just a mistake in the above sentence or did I not hear it right?

Answer 1

［あの信号を］［ひだりへ］曲がってください。

あの信号を continues to 曲がってください, not to ひだりへ. (I mean, it's not 「あの信号の/をひだり」.) あの信号を and ひだりへ both modify verb 曲がる.

あの信号を曲がる make a turn at that signal
あの信号をひだりへ曲がる lit. make a turn to the left at that signal → turn left at that signal

曲がる is an intransitive verb. Noun+を used with intransitive motion verbs, such as 歩く, 行く, 出る, 飛ぶ, 進む etc., can indicate the place of an action, the direction of a movement, or the point of departure, etc.

For more on this を, you could refer to:

• Explain how 向{む}く "to face" can take "上{うえ}" as a direct object using を?
• Making sense of transitive usage of 行く and 来る - 「を行く」 and 「を来る」
• この道をまっすぐ行ってください。 Why を and not で?

Answer 2

Mainly の is used for the possessiveness. Exact meaning in english is "of" or "belongs to".

In the case of を it's a object marking particle.

For the direction purposes, normally に　へ　で are used respectively. Other particles are very rarely used.