The McLean Museum and Art Gallery — now officially called the Watt Institution — is Greenock's main museum and the best starting point for understanding both the town and the Industrial Revolution. The James Watt collection is the centrepiece: tools, models, letters, and instruments that tell the story of the engineer who changed the world from this small Scottish port.
Beyond Watt, the museum covers the history of Clyde shipbuilding in considerable depth, with ship models, photographs, and equipment that document the industry that defined Greenock for over a century. The art gallery holds a modest but worthwhile collection of Scottish paintings. The building itself, a solid Victorian neoclassical structure on Union Street, is worth looking at from the outside too.