Batonis Castle is the main historic sight in Telavi: a walled royal complex that served as the residence of King Erekle II and the later Kakhetian court. Its Persian-influenced palace, defensive walls, and museum collections give the town more weight than a simple wine-country base.
The castle sits right in the centre, so it works as the natural first stop on a Telavi walk. From here you are a few minutes from the old streets, the plane tree, and the wine bars around the main square.