"Anderson's Piano" is a set of wires and signals at the Pass of Brander, near Falls of Cruachan in Scotland, that try to detect when there might be a boulder on the track. They're 140 years old, and so far no-one's been able to find a better solution — but they're working on it.

Thanks to all the team at Network Rail and Scotland's Railway: https://scotlandsrailway.com/
Edited by Michelle Martin   / mrsmmartin  

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