Definition of "viaduct"

[…] St. Bede's at this period of its history was perhaps the poorest and most miserable parish in the East End of London. Close-packed, crushed by the buttressed height of the railway viaduct, rendered airless by huge walls of factories, it at once banished lively interest from a stranger's mind and left only a dull oppression of the spirit.

1918, W[illiam] B[abington] Maxwell, chapter VII, in The Mirror and the Lamp, Indianapolis, Ind.: The Bobbs-Merrill Company

The L.C.C. [London County Council] considers viaducts in London objectionable and a hindrance to town planning and would like to abolish all the Southern Railway lines on viaducts in South London. [Nothing much happened, they still exist.]

1944 January and February, C. F. Cobon, “The County of London Plan”, in Railway Magazine, page 24