Hill
Just because there's a mausoleum on this hill doesn't mean it isn't still a hill. (It is. It's still a hill.)
きゅうりょう
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
今日は天気が良かったので、矢田丘陵を歩きました。
The weather was nice today so I walked the Yata hills.