The most common and most likely answer to this crossword clue is the 8 letter word HELSINKI
I've seen this crossword clue in The Guardian
H
E
L
S
I
N
K
I
More clues leading to the result HELSINKI
- Curious elk is in front of Huckleberry Finn’s home, perhaps
- City brothels in kinky shows
- Go down in the pit briefly by India's capital
- Link she forged with one capital city
- Man in silk changing foreign capital
- Foreign city hospital lies in ruins, flooded by liquid
- City‘s removing 50% of helipads: let that sink in
- City brothels in kinky houses
- Ambassador fashioned links with one city
- Chap left to abandon one capital
Buddy explains!
The straight part
We know that "capital port" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case capital port = helsinki.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.