Trains are one of the safest ways to travel, but it hasn't always been like that. In this talk I will introduce the basics of railway signalling, and look at how it has evolved over time - often in response to accidents and near-misses. You will find out how a single stray wire caused an accident that killed 35 people, why leaves on the line cause such a problem for the railways, and how signalling systems are designed to deal with the inevitable human error. Working from the early days of the railway to the present (and future), the talk will take you through a number of accidents, their causes and the improvements that were made after the accidents.

This talk is suitable for any level of knowledge about railways - it aims to be understandable for complete beginners, and still have some interesting parts even for railway geeks.

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