The Royal Crescent is Britain's most complete Georgian terrace and it costs nothing to see. The thirty houses sweep in a single unbroken arc across the hillside above Bath, all built between 1767 and 1774, all still occupied. No. 1 Royal Crescent is now a museum open to visitors; the rest are private homes that have been lived in continuously for 250 years.
The lawn in front of the Crescent (Royal Victoria Park below it) is where Bath comes to sit on a decent afternoon. The view from the park back up to the Crescent is the classic shot; walk around the back of it for the less photographed and more interesting rear elevation.