When the Sacred Sky Watch is motivated, its production is not only doubled but it also produces one forge point. The production is also boosted by enthusiastic population and by boosts of certain great buildings. The building's coin production can be plundered if it isn't motivated.
This building requires a road connection.
It is a result of InnoGames' attempt to make rewards from Guild Expeditions unique, thus replacing Shrine of Knowledge as a GE reward. Its properties are almost the same as the SoK giving the same amount of population and coins per square. However, its Forge Point production effectiveness is 50% less.
The Sacred Sky Watch can be obtained from the Rare Jade Relic during the Guild Expeditions. It can also be obtained as a reward for completing the last encounter of level III and IV of the Guild Expeditions.
The Sacred Sky Watch can be upgraded by Sacred Sky Watch Upgrade Kit item. To upgrade the Sacred Sky Watch, use the Sacred Sky Watch Upgrade item on the Sacred Sky Watch that is already situated in your city. Its upgraded version will then be placed directly on the same spot in your city and the production timer will not be reset. Note that the upgraded building will be from your current era, even if the old one was from one of the earlier ages.