Taman Sari (the Water Castle) , constructed over a period of many years by Sultan Hamengkubuwono I, and then abruptly abandoned after his death. It is now a series of pleasure gardens rebuilt in the 18th century for the sultan and his family. The complex once boasted lighted underwater corridors, underground mosques and meditation platform floating in a sea of lilies. The most remarkable structure at Taman Sari is the Sumur Gumuling, commonly refer to by the local as the mosque.
The bathing pool for Hareem of Sultan. From the other side of it, the Sultan watch and observed his hareem from a small tower, he would throw a flower to the bathing pool and let his hareem struggle in fun to get the flower. And the winner would stay with the Sultan for "honeymoon" in a special room in the palace.