In Iceland there is a lot of interesting churches. The turf one called Hofskirkja (Church in Hof) is probably the cutest one. So if you are travelling between Vík í Mýrdal and the Glacier Lagoon, you can consider to stop here. And the toilets are just meters away!
Fom the ring road turn to Hof and you´ll find it there quite easily. Park at the parking lot.