The medieval H?e castle (H?een linna) is located in the city.
There has been a settlement in where the city now stands since the Iron age. In the 11th century the entire province was under influence of both Sweden and Novgorod, and the Castle of h?e (h?een linna from where the finnish name H?eenlinna comes from). A village was born during time near to the castle to provide services and goods to inhabitants.
The village was granted city rights in 1639 and soon after that the King of Sweden moved it couple of kilometres south where it now stands.
The city is has always been known for its excellent schools and academies in where many famous finns have studiet.
The composer Jean Sibelius was born in H?eenlinna.
Poet Eino Leino graduated from high school in H?eenlinna.(H?eenlinnan Lyseon Lukio = H?eenlinna Lyseo Upper secondary school(Am. higschool)