The Carnon Viaduct was built for the Cornwall Railway's Truro to Falmouth line which opened in 1863. At that time it had timber spans carried on stone piers. A replacement, all stone and brick viaduct, opened in 1933 but the original stone piers (with one exception) still stand alongside.
<a href="//commons.wikimedia.org/wiki/User:Geof_Sheppard" title="User:Geof Sheppard">Geof Sheppard</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>