Directly opposite Tairua on the south bank of the river's estuary is the smaller settlement of Pauanui. The two settlements are 30 kilometres east of Thames although the town has closer connections with the sea side resort town Whangamatā. Several islands lie off the mouth of the river, notably Slipper Island to the southeast and the Aldermen Islands 20 kilometres to the east. Mount Paku is an extinct volcano that lies by Tairua Harbour. It was thought to have formed the Alderman Islands.