Shuri Castle is not a ruin, but a fully reconstructed castle with manicured walls and colourful wooden buildings - even the caretakers are dressed in historic costumes. Shuri was the capital of the Ryukyu Kingdom. The original castle was built in the late 1300s, but wars and fires had it destroyed multiple times over the centuries. The current reconstruction is from 1992 and the new buildings are actually rised above the original ruins to protect them. Parts have been rebuilt in the original style, while others are more museum like.
Many consider Shuri Castle to be the crown jewel of the UNESCO World Heritage Site, which also includes other historical sites on Okinawa from the Gusuku period (12th-15th century).