Langa Langa Lagoon or Akwalaafu is a natural lagoon on the West coast of Malaita near the provincial capital Auki within Solomon Islands. The lagoon is 21 km in length and just under 1 km wide. The "lagoon people" or "salt water people" live on small artificial islands built up on sand bars over time where they were forced to flee from the headhunters of mainland Malaita.

Malaita is the primary island of Malaita Province in Solomon Islands. Malaita is the most populous island of the Solomon Islands, with a population of 161,832 as of 2021, or more than a third of the entire national population. It is also the second largest island in the country by area, after Guadalcanal.