Freeciv/Codex/City Improvements


 * Airport
 * Aqueduct
 * Bank
 * Barracks
 * Barracks II
 * Barracks III
 * Cathedral
 * City Walls
 * Coastal Defence
 * Coinage
 * Colosseum
 * Courthouse
 * Factory
 * Granary
 * Harbour
 * Hydro Plant
 * Library
 * Marketplace
 * Mass Transit
 * Manufacturing Plant
 * Nuclear Plant
 * Offshore Platform
 * Palace
 * Police Station
 * Port Facility
 * Power Plant
 * Recycling Centre
 * Research Lab
 * SAM Battery
 * SDI Defence
 * Sewer System
 * Solar Plant
 * Space Component
 * Space Module
 * Space Structural
 * Stock Exchange
 * Super Highways
 * Supermarket
 * Temple
 * University