Firetuner Civ 5
Contents Game InfoAny group of 10 or fewer water tiles completely surrounded by land. Base yield:2 Food.Lake is considered a tile for moving purposes.The special building adds a +2 Food bonus to each Lake tile worked by this city.StrategyLakes are terrain features found anywhere on land. A lake is every single water tile, or any several water tiles, which are completely surrounded by land, and aren't so numerous as to be considered an inland sea.
The difference between a Lake and an Inland sea is that the lake has, which it provides to the surrounding tiles (besides having a different Base yield).Civilopedia entryA lake is any body of water ten tiles or smaller in size that is completely surrounded by land tiles (any larger body of water is considered ocean). When worked, lakes provide 2 food and 1 gold to nearby cities.
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Lakes are sources of fresh water, allowing the construction of farms on adjacent hills and tundra. Farms next to fresh water receive an additional +1 food when the technology is researched.See also.