It's easy to wade (or kayak) across to the uninhabited islets at both low and high tide and spend a day relaxing on the quiet beach and looking back towards the mountains of Rarotonga. Snorkelling in the lagoon is good only for marine life - there's no coral here and the lagoon is only waist deep in most places which makes it easy for beginners.
Muri Beach has the highest concentration of accommodation on Rarotonga from a small 65-room resort to lots of self-catering bungalows. There's several independent restaurants and takeaways in the Muri Area. Climb the hill opposite Pacific Resort for excellent views of the lagoon and islets.
On the north end of Muri opposite Motutapu islet is Avana Passage where the Cook Island Maoris departed in double hull catamarans to colonise New Zealand. The passage here is the best and most reliable surfing spot in the Cook Islands and allows entry for protected anchorage for yachts and motor boats. Inland from Avana is the extremely attractive and peaceful Turangi Valley. A dirt track leads almost 3 miles inland into the heart of Rarotonga and makes for excellent walking past small plantations and lush tropical forest. There's a lovely church a mile or so north of Muri which is built from limestone blocks and makes a good choice for a Sunday Church service.