Old Maps of Helsinki along with Fortification Plans

I was looking for something else but came across these gems. They are maps commissioned by the Swedish military. I have provided a small explanation for each in order.

1. Meant for the navy due to water depth plotting. You can see the initial plan for the fortification of the bay was to be in Katajanokka. (1739)
2. A plan for the aforementioned fortification. (1740)
3. An alternative plan centered on the hill in todays Kaivopuisto and it’s outlying islands like Harakka. (1743)
4. After the construction of Suomenlinna further plans were drafted to "protect the galley fleet" that harbored within the relative safety of it. I assume the aim of these new fortifications would have been to protect the galleys from landward threats. (1767)
5. Meant to depict different avenues for troop movements depending on the season. Provides a good capsule of nature and topography surrounding the city. (1776)

Photos are from the Military Archives of Sweden, Stockholm

Here you can browse these maps yourself.