We were lucky enough to stay at Lake Tekapo for three nights in March 2013.
The Church itself is truly adorable but the best time view the church and soundings is either early in the morning or late afternoon going on sunset. The colours of the sky light up and the clouds start rolling over the hills creating a mystical atmosphere. Even better stay the night, or two, and make the most of the star gazing :-)
Like many people have said go inside the church and remember to make a small donation to the lovely old man that looks after the premises during the week.
one last point the church closes bang on 5pm - I saw many people turn up to look around but were disappointed as they couldn't go inside.
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