The Uxbridge Historical Centre is a small local museum, useful if you want the town to feel less anonymous after a morning on the trails. Its collections cover township settlement, farm life, Quaker roots, and the railway era that helped connect Uxbridge to the wider region.
It is not a major museum, but it is the right scale for the place. Pair it with lunch in town or with the Thomas Foster Memorial rather than making it the whole outing.