Lake Tekapo is a gorgeous blue lake southwest of Christchurch. It is renown for it’s milky blue waters (made blue by rock flour which is created by the grinding of rocks by the glaciers) and is part of the UNESCO dark sky reserve. Unfortunately it was overcast the whole time we were there so we didn’t get to see the night sky. Also well known is the church of the good shepherd which sits on the edge of the lake.
There is also a walk up to the observatory (which was closed) on Mt John with spectacular views over the surrounding countryside.