The Palace, on the east main street is a series of large and rambling buildings of fine masonry, built partly by the Nayaks around 1550 AD, and partly by the Marathas. The entrance is by way of a large quandrangular courtyard. The encircling walls are pierced by big gateways to the north and east. The courtyard leads to a many-pillared hall. A small inner courtyard gives access to a large one.
On the southern side of the third quadrangle is a vimana like building, 190 feet high with eight storeys and it is the Goodagopuram. This was the palace watch tower and also the armoury of the Thanjavur Kings till 1855 A.D.
The two Durbar Halls of the Nayaks and the Mahrattas and the Raja Sarafoji Saraswathi Mahal Library are the chief sights of the Palace. The Saraswathi Mahal Library has remarkable collection of about 30,433 sanskrit and other vernacular palm leaf manuscripts and 6,426 printed volumes, besides a large number of journals. The library is the effort of the three hundred years of collections by the Nayak and Mahratta kings.
Madamaligai is the tower which rises from the palace roof beyond the Goodagopuram. It has six storeys. It is believed that this was built by Nayak ruler to enable him worship Sri Ranganatha of Srirangam every mid-day. This many storeyed tower was destroyed by lightning and was subsequently repaired and preserved.
The Sangita Mahal or the Music Hall is a miniature of the surviving court of Thirumalai Nayak's.