ここ, そこ, and あそこ are pronouns for locations which mean "here", "there(near you)", and "over there", respectively. Place nouns which are used in this pattern include such words as じむしつ(administrative office), としょしつ(library [room]), and こうえん(park).
ここは じむしつです。
This [place] is the administrative office.
Cf. Lesson 1-4: ko-so-a-do words
