Fact · North Uist
The ground under your feet is the oldest in Britain
The rock under Uist is the oldest in Britain. Lewisian gneiss formed up to three billion years ago, before anything complex lived on land. The Natural History Museum flew to the Outer Hebrides to fetch a lump for its London garden.
Uist, like the rest of the Western Isles, is built on Lewisian gneiss, a banded grey and pink rock that formed between three and 1.7 billion years ago, deep in the Earth's crust, long before complex life reached land. It is the oldest rock in the UK. The Natural History Museum in London wanted a piece for the evolution timeline in its new gardens, so in 2024 its scientists flew to the Outer Hebrides, landed on a beach, and chose a six-tonne boulder that 'glows with colour when wet'. Every beach in Uist has smaller ones for free.
Sources / notes: Natural History Museum https://www.nhm.ac.uk/discover/the-search-for-the-uks-oldest-rock-in-the-outer-hebrides.html Wikipedia: Lewisian complex https://en.wikipedia.org/wiki/Lewisian_complex