Canal tunnel

A canal tunnel is a tunnel for a (shipping) canal. The longest canal tunnel in the world is the Rove Tunnel in France, currently disused. The proposed Stad Ship Tunnel in Norway, while shorter, will be significantly wider and deeper, as it is designed to accommodate seagoing vessels.

The oldest canal tunnel in the world is the Malpas Tunnel also in France, built in 1679.

In some canal tunnels the towpath continues through the tunnel. In other cases, especially on English narrow canals, there is no towpath. The horse would be led over the hill and the boat would be propelled by legging.

The term "canal tunnel" does not seem to be commonly applied to tunnels used to conduct water (for irrigation, water supply, etc.), such as the 48-kilometre-long Arpa-Sevan tunnel in Armenia (see List of longest tunnels), or a number of tunnels on the Irtysh–Karamay–Ürümqi Canal in China. For those, the term water tunnel is more commonly used.

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