Roald Dahl Plass is a public space in Cardiff Bay, Cardiff, Wales. It is named after Cardiff-born author Roald Dahl, and is located on the coast along the south of the city centre.

The area is home to the Senedd (Welsh Assembly Building) and the Wales Millennium Centre (Wales’ premier performing arts centre).

The bowl-like shape of the plaza makes it a popular amphitheatre for hosting open-air concerts.

• This area was one of the docks for a thriving coal port during the latter half the 19th century and much of the 20th century.
• With the redevelopment of the former docklands, Roald Dahl Plass was opened in April 2000 and is an oval shaped open space surrounded by illuminated pillars and plenty of places to eat and drink, and is often used to host concerts and other events.
• At the northerm end is the Water Tower, which stands at approximately 70 feet (21 metres) high with a constant stream of water running down the metallic fountain.
• The tower is well known to viewers of the Doctor Who spin-off series Torchwood, whose headquarters are located below it.