|Unit type||Medium naval unit|
|Creation time||Rather slow|
|Line of sight||Medium|
|Movement speed||Rather slow|
The Trieres is a large warship which carries more rowers and oars than other smaller vessels, making it capable of greater firepower as well as hull strength compared to the smaller Lembos or even the lowly Xorileum used by Germanic tribes. By far and large, the Trieres is the fastest warship amongst all others, and provides a good balance between cost and effectiveness. The only problem is that it suffers from fairly poor rates of fire and also has a fairly low range, being only slightly more powerful than archer units and as such can be easily outclassed later on by the larger polyreme-class warships and their multiple complements of long-ranged artillery.
As such, the Trieres has as its primary function in the more sophisticated navies of the Mediterranean as heavy escort vessels, as well as to amass naval supremacy by virtue of it being fairly powerful if amassed in large numbers as escorts for the larger polyremes. Ideally, a small fleet can be assembled of about five to ten Trieretai, with at least three of the larger siege ships in tow to function as support.
Queen of the seas for centuries, the trieres or triremis (literally in Greek, "three-oar") was the backbone of most Mediterranean navies prior to the rise of Alexander the Great, and consisted of a warship propelled by three banks of oars, hence its name. Thought to have been first introduced by the Phoenicians of the Middle East, the triremis is often heavily associated with the Athenian Greeks, who under the leadership of Themistokles (524–429BCE) established a fleet of such warships for the Athenian republic, allowing Athens to embark on a journey towards commercial domination and glory.
At the height of Athenian power, triremes were as wide as 4 metres, and also had a deck length of roughly around 40 metres, and with sufficient exertion were rather speedy vessels. By the post-Alexandrine era, however, newer and larger vessels as well as economically lean times meant that the triremis would soon fall out of favour with Mediterranean navies who like the Seleucids and Egyptians preferred to build larger vessels, or recruit lighter but cheaper ships such as liburnae and lemboi.