Great Falls, Waterfall in Waterdown, Hamilton, Ontario, Canada.

Great Falls is a waterfall on Grindstone Creek in Waterdown, part of Hamilton, Ontario, where the creek crosses the Niagara Escarpment. The drop is about 10 metres high and roughly 5 metres wide at the crest, a ribbon-type fall whose stream forms a thin band of water. It lies in a wooded ravine of the Grindstone Creek valley.

The Niagara Escarpment's dolostone layers, formed some 400 million years ago, create the ledges over which Grindstone Creek drops at Great Falls. The falls lie within the former town of Waterdown, which amalgamated with Hamilton on January 1, 2001. The Hamilton Conservation Authority lists Great Falls among the city's roughly 100 waterfalls.

The valley earned the name Smokey Hollow from industrial smoke that filled the area during the 1800s. Today, visitors can trace these industrial roots in how the land has been shaped and recovered.

You can reach this waterfall by walking trails connected to the Bruce Trail system running along the Niagara Escarpment. The paths are generally well-marked, but surfaces near the water can be slippery, especially after rain.

This waterfall is part of a larger network, as the Hamilton region is home to more than 100 falls throughout the area. This concentration of waterfalls makes the region uncommonly water-rich compared to other parts of the province.