Lower Town (also spelled "Lowertown" is a neighbourhood in Rideau-Vanier Ward in central Ottawa, Ontario, Canada, to the east of downtown. It is the oldest part of the city. It is bounded roughly by Rideau Street to the south, Sussex Drive and Ottawa River to the north, the Rideau Canal to the west, and the Rideau River to the east. It includes the commercial Byward Market area in the south-western part, and is predominantly residential in the north and east.