Building A Tunnel Thru A Hill

How do you build a tunnel through a hill?  I get asked this question a lot so I am providing an easy to follow picture tutorial for anyone to follow.  Just follow the steps and your sims will have their very own tunnel in no time!  We will be working with settings in build mode, until the end where you need to find one thing in buy mode.  If you are not familiar with these settings, you may want to look at them and see the names of each setting before we begin.

Items needed to complete the tunnel:  Into The Future to finish the top

Before you begin, determine just how long you want your tunnel to be and which arch you wish to use as an opening at each end.  Count the squares on the grid to know exactly how wide you need to make the hill.

  1. Go into build mode, choose the raise terrain tool.  Raise up the land to be taller than the height of a wall in a straight line for the length of the tunnel. I want my tunnel to be 10 squares through the hill, so I raised up the land a little deeper than this. Then use the soften terrain tool to smooth out the hill to look something like this.


2.  Next you need to flatten the land going up to the hill.  Choose the level terrain tool, start from a level square and pull back towards the hill to flatten the land.  Keep in mind you need the hill as wide as the length of your tunnel you have chosen so don’t flatten past that point.  Flatten the land on both sides of the hill.


3.   Keep in mind you need the hill as wide as the length of your tunnel you have chosen.  When you flatten the other side, count the squares over the curve of the hill and flatten the land on the other side to the exact length of your tunnel. I want my tunnel to be 10 squares through the hill.


4.  Next choose your arch and place it on the ground to determine how many squares it takes up.  I’ve chosen the cellar arch and I see here it takes up 2 squares.  Which means my tunnel will be 2 squares wide when finished and I need to draw the tunnel 4 squares wide.  If you want your tunnel to be wider than 2 squares on the grid, you will need to make it 6.  But I am jumping ahead just a bit.  I will be making mine 4 grid squares wide.


5.  Choose the wall tool.  Start on a level square and draw the wall straight thru the hill to the exact length you want the tunnel to be.  Then draw another wall using the same method 4 or 6 squares apart from the first wall, making it parallel to the first.


Then close in each end to make a rectangle and the exact length of your tunnel you need.  If you have drawn your walls in the front of the tunnel beyond the curve of the hill, then delete sections of the wall till they meet the beginning of the curve as show above.


5.  Okay here is the tricky part.  You will need to flatten one square next to the  tunnel.  Use the raise and lower terrain to get something relatively flat.


You want the flat square close to the height of the wall.

6.  Next we have to type in the cheats.  Press Control + Shift + C at the same time and the cheat box appears at the top left of your screen. Type in testingCheatsEnabled true just as I have show you here and hit enter.  Then press Control + Shift + C again and type in constrainfloorelevation false then push Enter.  This is the CFE cheat to alter terrains.

7.  Using the level terrain tool and using that flat-ish square we just made we are going to level the land straight across from one side to the other.  The walls will raise so don’t panic.  We will fix those after.  To level the ground, you will need to page down or level down so the wall grid is not showing.  Otherwise it will not work.  Hint:  if the level terrain green square stops showing up, just click on lower terrain, then click back to level terrain.



8.  Next we need to lower the walls.  Use the page up on your keyboard to bring back the wall grid.  Choose a flat square close to the edge where the walls are not raised.  Use the level terrain tool again, start at the flat square and highlight the green across to the back covering all the raised walls.  This may take a few times to get the walls completely flat.  It’s tempermental.


Now it will look like this.


I like to wrap the dirt around the ends one square each by using the level terrain tool.  It will raise the walls when you do this, so just bring back the wall grid by using page up and then level the wall again.

9.  Its time to turn off the cheat.  Push Control + Shift + C to bring up the cheat box.  Push the arrow up on your keyboard and the cheat you last typed will appear.  Change false to true.

10.Its time to level the ground inside the tunnel.  You will level the ground to the width of your arch.  Mine is 2 grid squares and so that is what I will do.  Use the level terrain tool to do this.


Then page up to look for a roof the game will automatically put on.  Delete the roof.


Now add your arches on both ends.


11.  We want flat walls inside, not slanted.  So next we draw in walls.  Make sure the wall grid is off before doing this.


12.  Our tunnel is ready for a roof.  Page up to bring back the wall grid, which should be a grid completely across the top.  If by chance it doesn’t go across the top, leaving gaps, remove the arches and draw a wall down the middle of he tunnel like this:Screenshot-008.jpg

Once the grid is complete, remove the middle wall you drew in.  Go into Roofs section of build mode and choose the flat roof section: fullscreen-capture-182017-123548-pm-bmp


Doesn’t look all that good yet does it?  Well here is how I finish it off.  Go into buy mode, choose Decor, then rugs where you will find the Nature’s Soil rugs from the Expansion pack Into The Future.  Cover the top with them.


These rugs allow you to plant anything on top of them. But first we must finish the rest.

13.  Go back into build mode and choose the soften terrain tool.  Soften the hill around the entire area to bring down the high points and smooth it out.

Now you can decorate the top of the tunnel.  Begin by adding trees, plants or even rocks. You will need to use the cheat moveobjects on to place items on top of the tunnel. Use the alt key on your keyboard to slide things into place.

If you don’t have Into the Future, you can cover the top with rocks in build mode.  To do this, you will definitely need the moveobjects on cheat, as rocks can only be placed on the ground.

Make sure you turn the cheat off when you are done!  moveobjects off

14.  Lastly, the walls and floor need decorated.  I like the rock wall covering as I think old when I think tunnels.  You may want brick with a more modern look.

To do my floor, I choose to use terrain paints in build mode.  I created this look by using two different paints: gravel and pebbles


I also added lights on the inside as well.

So I just did this quick and I’m sure you will do better but here is a rock version:


This is my tunnel in game right now.  It’s still a work in progress.


I used the terrain pain to colour the ground around the tunnel to look like rock which makes it blend more into the hill.

I hope this helps and you find the tutorial easy to follow.  Any questions please ask!

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