This is a jukugo word, which usually means on'yomi readings for the kanji. If you know the readings of your kanji you'll know how to read this as well. 中 does have a strange reading, though, which is じゅう. This is basically just ちゅう changing to ぢゅう, but since ぢ is very rare it just switches to じ and you end up with じゅう. That's called rendaku.
The sky in this town is dull all year.
Tofugu employees work twenty four seven, year round.
It rains year round in this country and my wife complains about it year round as well.