It is the widest range of ships the festival has had.
They included the eye-catching Mexican ARM Cuauhtémoc. The steel-hulled sail training vessel, named after the last Aztec emperor, allows the cadets on board to hone their skills.
The Royal Navy’s Sandown Class minehunter HMS Penzance put in an appearance. She primarily neutralises underwater threats, but also has a secondary role as an offshore patrol vessel, helping to secure the UK’s waters.
From HMS Penzance, Sub Lieutenant Matthew Grayson says it is important to engage with the public and explain what the Navy is doing:
"I think a lot of the time they don't have as good an awareness as they should have, of the roles that we play, because we're overseas doing our job".
Commander Rob Milligan, Senior Naval Officer Northern Ireland, said it is a great chance for visitors to get an insight into life on the ships: "In Northern Ireland, the Royal Navy's got quite a small footprint.
"We've got a small naval reserve unit here, but otherwise the Navy is really out of sight and out of mind.
"To put a vessel alongside in a place like Queen's Quay here, right in the city centre and open to the public is a great opportunity".
The Irish Defence Force was represented by LÉ Samuel Beckett.
The offshore patrol vessel is designed to cope with the rough waters of the North Atlantic off the west coast of Ireland.
LÉ Samuel Beckett has been involved in the rescue of more than 2,300 migrants in the Mediterranean Sea.