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Why is the Channel Tunnel really three tunnels?

The Channel Tunnel’s name hides a three-part arrangement. Two tunnels carry trains, while a smaller service tunnel runs between them beneath the seabed.

3–5 min

Questions you could explore

  • Why might a tunnel system need a route that ordinary passenger trains never use?

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What happens to water before it reaches the tap?

Clear-looking water and drinking water are not necessarily the same thing. In Uisce Éireann's representative surface-water process, clarification, filtration, and disinfection deal with different parts of the treatment problem.

4–5 min
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What do the two parts of an Eircode tell you?

Ireland's seven-character address code combines a routing key with a unique identifier. The operator's public example, A65 F4E2, shows how a shared first part and an individual second part do different jobs.

2–3 min
Cities and transport

How does a canal lock lift a boat without lifting machinery?

A boat inside a lock rises when the water around it rises. By filling or emptying the enclosed chamber, a conventional lock brings the boat to the level of the next stretch of canal. The gates contain the water; they do not hoist the boat.

3–5 min
Why is the Channel Tunnel really three tunnels? | Speech Topic | speaking.app