Actual effect of railroads?

[Superior Man]

I'm unsure about this. It costs an unit 0 MP to move on them, yes. That is clear. But what about the economical effects? I read various descriptions about them, in forums, Civ II manuals, strategy guides etc.

Most state that every square produces one additional shield after the city built Superhighways. But I wasn't able to tell a difference from looking at the city screen between a square with railroads and another one with roads. Otherwise, both squares were identical, e.g. irrigated, regular grassland etc.

Could someone tell me the truth?

 

[Terrapin]

You have asked about two separate things, Railroads and Superhighways.

1. Railroads are an improvement which can be built on any square. As you say, any unit from any civ can move from one Railroaded square to another for a cost of 0 move points. When you build a Railroad on a square within a city radius it increases shield production of that square by 50%. Because Civ2 rounds all fractions down, this mean that the Railroad has no effect on a square which produces 0 or 1 shields.

2. Superhighways are a city improvement which increases the number of trade arrows produced by Roaded (including Railroaded) squares within that city's radius by 50%. Again, because all fractions in Civ2 are rounded down, this means that Superhighways have no effect on squares which produce 0 or 1 trade arrows. Note that this means that Superhighways increase trade arrow production from 2 to 3 on Roaded flatland (grassland, plains, desert) in a city which is part of a Republic or Democracy or which is celebrating under Monarchy, Commie or Fundy. Also note that Superhighways do affect Roaded trade producing specials such as Wine and Silk even though the roads themslves do not produce the trade. Finally, Superhighways increase the payoff from delivering caravans when they exist in the sending city, the receiving city or both.

 

[Superior Man]

You're right, I mixed those two things up. I guess the downrounding is what always made me curious about if there is an effect at all. Thanks for the answer.

 

[ElephantU]

One other item to mention: a "critical path" road or rail link between two cities with a trade route link can increase that particular route's trade arrows between 50% (road) and 100% (rail). Determining the "critical path" between the cities is tricky - there are some threads on the theory, and sending a unit in one city to the other city via the GoTo command "generally" traces out the route, but there are a few exceptions and it must be done before roads and rails change the way GoTo calculates. Note also that the "critical path" route from city A to city B is NOT the same path as from city B to city A. You have to read the details in the threads to understand why. I still don't...

 

[Terrapin]

Thanks, 'Phant, I forgot about the critical path stuff. I do not even attempt to Road/Railroad critical paths. I just try to build roads/railroads all over the place. On my continent, I just cover every single square.

 

[Zhoragh]

Again, because all fractions in Civ2 are rounded down, this means that Superhighways have no effect on squares which produce 0 or 1 trade arrows.

This may be an oddity of the Mac version, but I've tested and discovered with absolute certainty that Superhighways *DO* increase trade on squares that have only 1 trade. The values of odd numbers are apparently all added together first, and then increased. The simplest test I had that proved this was that a city with road squares, none of which produced more than 1 trade, had some total level of trade. I scrapped the superhighways, and the trade decreased. I speedbuilt it for the next turn, and - sure enough! I had that original trade value back. Railroads and Farmlands round down as you said, though.