Cities: Skylines Sea Fortress Unlock Guide (Get a Level 5 Park Area)

Sea Fortress Building in Cities: Skylines
Sea Fortress
Cost to Build ₡100,000
Upkeep ₡1,200/week
Entertainment Value 150
Noise Pollution 50

The Sea Fortress is a level 4 unique building that you can only get with the Cities: Skylines Parklife DLC. To unlock it, you must achieve two things:

  • Reach the Busy Town population milestone
  • Have a Level 5 park area (Parklife DLC)

Once these requirements are met, you’ll be able to build the Sea Fortress from the level 4 unique buildings menu for ₡100,000.

It provides 150 entertainment value and produces 50 noise.

It is also one of the requirements for the Castle of Lord Chirpwick monument.

Building a Park Area

If you don’t have an existing park area yet, create one by going to Districts and Areas, and selecting Paint Park Area.

Paint over the terrain where you want your park to be, making sure there is at least one road connection adjacent to it.

Also, since you’ll need to upgrade this park to level 5, you’ll want to provide plenty of space for it.

The Paint Park Area tool from the Districts and Areas menu. / Cities: Skylines
The Paint Park Area tool from the Districts and Areas menu.

Once you’ve marked out your area, go to Parks & Plazas, and click on the tab of your desired park type:

  • City park
  • Amusement park
  • Nature reserve
  • Zoo

Select the main gate of your chosen park type (either the regular size or small main gate will do), and place it along the road. This will automatically designate that area a level 1 park area of your chosen type.

Go to Parks & Plazas (1), then select the tab of your chosen park type. / Cities: Skylines
Go to Parks & Plazas (1), then select the tab of your chosen park type.

Now, it’s time to upgrade your park to the highest level, which is 5.

Leveling Up Your Park Part 1: Increasing Entertainment

Leveling up your park area requires you to hit milestones in terms of total visitor count, and the entertainment value of your park.

You can check your level progress by clicking on the name of your park on the map. / Cities: Skylines
You can check your level progress by clicking on the name of your park on the map.

Entertainment basically refers to the amount of features your park has. Each park building or decoration you place within your park adds to your total.

You unlock more park buildings and decorations as you level up. You may build several instances of particular buildings to accumulate enough entertainment points.

For example, each gazebo provides 60 entertainment points, so these add up to 300. / Cities: Skylines
For example, each gazebo provides 60 entertainment points, so these add up to 300.

Decorations such as trees, benches, and flower beds also contribute to the entertainment value of your park, so add plenty!

Details such as concession stands, benches, and trees add to your entertainment value. / Cities: Skylines
Details such as concession stands, benches, and trees add to your entertainment value.

Leveling Up Your Park Part 2: Getting More Visitors

So you’ve built a nice-looking park with plenty of features, but not a lot of people are visiting it.

Not only will this slow your unlock progress, but it can also leave your park unprofitable.

Here are a few things you can do:

Tip #1: Place Your Park in an Area with Plenty of Foot Traffic

It’s always a good idea to place your park areas near plenty of residential zoning.

For one thing, it will boost the land value in the nearby area and the happiness of those living there.

Secondly, if you place one main gate and one side gate on opposite sides of your park, some of your citizens may start using the park as a pedestrian shortcut, significantly boosting your visitor count.

This park’s footbridge is a convenient path from a residential district to offices, making it a popular pedestrian route. / Cities: Skylines
This park’s footbridge is a convenient path from a residential district to offices, making it a popular pedestrian route.

Tip #2: Provide Plenty of Public Transport

Having public transportation options nearby, such as a bus stop, or a metro or monorail station, can also encourage more people to visit.

Of course, this isn’t a requirement.

But it does help a lot in unlocking the Sea Fortress.

Liz Villegas

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Liz is a writer and photographer with a love for building and strategy games. Her spare time is often split between lifting, reading, drawing, annoying her dog Mr. Porky Butt, and squinting at stat tables on the wiki pages of whatever game she's currently playing.