Suburb
Outskirts
Suburbs on the outside of town are still suburbs. They're sometimes called the outskirts of town too.
こうがい
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
都心と郊外、どちらに住みたいですか。
Would you rather live in the city center or the suburbs?