Hafnir
The town Hafnir owns the second most land in the Reykjanes peninsula and takes its name from two large farms Sandhöfn and Kirkjuhöfn which are now deserted. In Hafnir you can find remains of the oldest occupation in the peninsula dated back to the 9th century, you can also find an anchor from the ghost ship Jamestown that drifted ashore there in 1881.
Today fewer people are living in Hafnir compared to before but Hafnir was a big fishing village until the turn of the century in 1900. In the last two decades, an average of 80-120 people have lived in the area. In 1994, Hafnir Njarðvík and Keflavík merged into the municipality of Reykjanesbær.
Refrences:
https://ferlir.is/reykjanesbaer-throun-byggdar/
https://www.reykjanesbaer.is/is/stjornsysla/rnb/saga/hafnir
https://is.nat.is/hafnir/
https://reykjanesgeopark.is/is/destination/vogar-i-hofnum/