Simpleton Series: Joining tunnels and bridges neatly in SimCity 3000

Contributor/author(s): Simpleton

Some nice visual effects may be created by having high ground falling to a river and then a plain on the other side. If you want a road through this as well the overall effect can be marred by wasting too much space, or getting switch-backs, between the bridge over the river and the tunnel through the hill.

It is possible to have just a single flat road tile between the bridge and the tunnel (this will also work connecting double bridges with double tunnels) - but you will have to do some work and there are four main phases.

Note: This is one of the quirks of SimCity - we end up with an effect which looks as though a problem has been overcome brilliantly, but we have to do the civil engineering bit first and then create the 'problem over the works if we want things in exactly the right place!

The basic techniques come from articles on building bridges by Johnny Blaze and building side by side tunnels by Dave.

Phase 1 - Organize the terrain

Note: I am keeping this as a simple exercise to illustrate the basic technique.

1. Arrange your terrain so you have a 65 metre surface elevation each side of the river. The width of the river will dictate what type of bridge you are going to get.
2. The 'bridge side' of your intended tunnel will be the EXIT side of the tunnel. Ensure you have constant ground height between the initial terrain you want the flat bridge on and where you want the ENTRY side of the tunnel to be. This MUST be on a direct tile line between the two.

Phase 2 - Build the bridge(s)

1. The bridge HAS to be built first.
2. Build your single bridge by simply running the 'Build Road' tool from four tiles out on one side, across the river and onto the opposite bank enough tiles for the mouse cursor to go blue. Release the button and accept the 'Build Bridge' invite.
    
3. You will now have a 'flat bridge' and no earthwork to do
4. Bulldoze the road tiles except one single tile at the bridge entry portals
5. From the now flat bridge entry tiles use the 'Level Terrain' tool to check you have flat ground to the tunnel entry point you want and at least four tiles beyond this. Place one road tile at the mouth of where you want the other end of the tunnel to be if you need a marker.

Phase 3 - Build the tunnel(s)

1. From the tunnel entry go 3 tiles down the line of the tunnel. Engage the 'Raise Terrain' tool and give it 4 clicks.
2. Use the 'Level Terrain' tool to extend a berm along the length of the tunnel from entry to exit. Make the berm 2 tiles wide if you want a double tunnel.
3. Check both ends of the intended tunnel are where you want them.
    
4. Work from the opposite end of the intended tunnel to the bridge - if necessary reverse your screen view. Run a row of four road tiles across the entry marker road tile along the axis of the tunnel and onto the first slope of the berm. Release the button and accept the Build Tunnel invite.
    
5. The tunnel will automatically plug into the bridge with a flat one tile road section connection.
    

Phase 4 - Create terrain effect

OK - this is the bit you have been itching for. Use the Terrain tools to create the effect you wanted along the river banks and between the tunnel exit and entry. This could be mountains, or could be a split level inner city terrain - your choice and your imagination!

Notes:

• Exit Side of Bridge. You can use the Terrain tools to give you the terrain height you want on the side of the river opposite to the tunnel (See 'Changing Levels with Bridges') You could go up or down in terrain if you want, or go into another tunnel on that side.
• Bridge at Both Ends of a Tunnel. If you want to build a second bridge later at the other end of the tunnel then you have to do prior preparation very carefully in tile distance and ensure the tunnel outlet is dead flat, at least 2 tiles long down the axis of the intended bridge - and it still may not work. Build TOWARDS the tunnel mouth from the other side of the river.
• Tunnel from an Existing Bridge. If you cannot build the tunnel to the bridge then you MUST arrange the berm so you are 2 flat tiles short of the face to enable you to build the tunnel FROM the bridge. It only seems possible to get the single tile connection when working from the other end.
• Single Tile Connection to a Tunnel both sides of the Bridge. This is easy - just follow the above procedure and then repeat it from the other side remembering you have to build the tunnel TOWARDS the bridge to get the single tile connection.
• S Bend Tunnel/Bridge Connector. This may be of use to you when building in hilly terrain and you want additional detail visual features. It is for single tunnel/bridge interconnections. Follow the procedure given above but build the tunnel berm ONE tile sideways of the bridge axis. Go to one tile short of the bridge entry portals and build the tunnel. You will automatically be given an S bend interconnection.
   
• Double Bridge/Double Tunnel Connections. Exactly the same as above but overlay the 'double bridge' and 'double tunnel' building techniques - remembering to build the double bridge FIRST!

By combining techniques you can easily achieve what is in the following illustration with a few minutes work. This is a double bridge, double tunnel, interconnected by single flat road tiles and changing road height by 39 metres.