The Garden of Cosmic Speculation is at Portrack House, near Dumfries in South West Scotland. It is a private garden created by Charles Jencks.
The garden is inspired by science and mathematics, with sculptures and landscaping on these themes, such as Black Holes and Fractals. The garden is not abundant with plants, but sets mathematical formulae and scientific phenomenae in a setting which elegantly combines natural features and artificial symmetry and curves. It is probably unique among gardens, and contrasts nicely with the historical and philosophical themes of the less spectacular but equally thoughtful Little Sparta.