Kaiserslautern is about 2.5 times smaller than Atlanta.

Atlanta (map shows its 114 named neighbourhoods; the area covers the whole city) is approximately 350 sq km, while Kaiserslautern is approximately 140 sq km, making Kaiserslautern 39.86% the size of Atlanta.
Tip: This to-scale comparison of Atlanta vs. Kaiserslautern uses the Mercator projection, which distorts the size of regions near the poles.
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