YOU SAID:

I often go hiking into the mountains.

INTO JAPANESE

私はしばしば山にハイキングに行く。

BACK INTO ENGLISH

I often go hiking in the mountains.

INTO JAPANESE

私は山にいました。

BACK INTO ENGLISH

I was in the mountains.

INTO JAPANESE

私は山にいました。

BACK INTO ENGLISH

I was in the mountains.