Aotea Lagoon is an urban park on the eastern arm of Porirua Harbour, built around an artificial saltwater lagoon that fills and drains with the tide. It has lawns for picnicking, a children's playground, a miniature railway that runs on weekends, and a swan paddleboat hire — solidly old-fashioned, but well kept.
The lagoon is shallow and warms up enough to be swimmable in summer, which is unusual for the Wellington region. A walking path circles the whole lagoon and connects through to the wider Porirua coastal route. Free to enter; the paddleboats and trains cost a few dollars.