This is the 831st most frequent Icelandic word.
hafnarinnar
"Of the harbor" or "of the port" (genitive singular form).
In this sentence, "hafnarinnar" is the genitive singular form of "höfnin", indicating possession, referring to the surroundings of the harbor.
Ég sat á veitingastaðnum við höfnina með útsýni yfir hafnarinnar.
I sat at the restaurant by the harbor with a view of the harbor surroundings.
Here, "hafnarinnar" is used in the genitive singular to show that the pier belongs to the harbor.
Farþegarnir fóru í bátana sem biðu við bryggju hafnarinnar.
The passengers boarded the boats that waited at the pier of the harbor.
In this sentence, "hafnarinnar" is in the genitive singular, demonstrating possession, referring to the harbor being owned by someone.