Wonders

§ Wonders are the spectacular buildings, inventions, and concepts that have stood the test of time and changed the world forever. The Pyramids, Notre Dame Cathedral, the Statue of Liberty and Hollywood are all examples of wonders. Wonders require much time and energy from your cities, but once completed, they provide your civilization with many benefits.
§ There are two basic types of wonders: great wonders and national wonders.
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Great Wonders

§  Great wonders are unique; only one of each can be constructed during a game. For example, the Great Lighthouse is a great wonder; whoever completes it first is the only one who may possess its benefits. Great Wonders tend to be quite powerful indeed, but also extremely time-consuming to build.
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National Wonders

§  National wonders may be built once by each civilization in the game. That is, each civilization can have the Wall Street national wonder (though no civilization can have two of them). Each city may only build two national wonders, so be sure to plan ahead where you wish to put them.
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Constructing Wonders

§  Wonders are constructed in cities, like any other Building. If you can build a wonder, it will appear in your city build menu; just click on the wonder to get started. Note that only one city in your civilization can be building a single wonder at a time.
§ Losing the Construction Race: If another civilization completes a great wonder while you are in the process of building it, your construction ceases, and a certain amount of your production efforts are converted into gold. This does not occur with national wonders, since each civilization can build its own copy of those.
§ Wonders and Resources: Certain resources will allow cities to produce wonders of both types at double the usual speed. For example, a civilization that has Stone connected to its City Network can build the Pyramids at a much faster rate.
§ Civilization Traits: Leaders who possess the Industrious trait build all wonders at twice the usual rate.
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Effects of Wonders

§ Wonders have a broad range of effects. Some increase productivity; others increase income from trade. Some improve research, others make your workers build improvements faster. All wonders improve their home city's Cultural Output as well as the speed at which the city generates Great People.
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Capturing Wonders

§ If you capture a city with a great wonder, you gain possession of that wonder. If you capture a city with a national wonder, the national wonder is destroyed. If a city is destroyed, all wonders in that city are destroyed along with it. Great wonders can never be rebuilt once they are destroyed.
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Wonder Obsolescence

§ Some wonders can become obsolete over time. This obsolescence is caused by any civilization in the game learning a specific technology. When that occurs, the wonder's special effects vanish, but it still continues to produce culture. For example, the Great Lighthouse wonder provides a trade benefit to all coastal cities, as well as +8 culture to the city where it is constructed. The Great Lighthouse is rendered obsolete once any civilization gains the Steam Power technology, at which point the owner loses the Lighthouse's trade benefit but retains its +8 cultural output.
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