Aitutaki lacks Rarotonga's popularity and sheer physical beauty but it has charms all its own. It sits at one corner of a triangular lagoon dotted with lovely motu (small islands), and it's historically interesting, with a number of impressive pre-European religious meeting grounds there.
Arutanga is the main village - a sleepy place with a weathered 1828 CICC church, the oldest and one of the most beautiful in the Cooks, with lots of carved wood and stained glass windows. There are lots of funky little shops, and the view of the coastline from the end of the jetty is superb.
Avarua, the capital of the Cook Islands and Rarotonga's main town, lies in the middle of the northern coast. Avarua used to be a sleepy little port, very much the image of a South Seas trading centre, but it got spruced up for the 1992 international Maire Nui festival, and it's still looking good.