Thomas built is aqueducts over the Dee and the Cieriog valleys.
Pontcysyllte Aqueduct and Canal
The Pontcysyllte Aqueduct and Canal is a navigable aqueduct that is considered a masterpiece of enigineering during the Industrial Revolution. It was built by Thomas Telford and William Jessop, and completed in 1805. Cast iron was used for the trough, while the pillars are made of brick.
The aqueduct carries the Llangollen Canal over the valley of the River Dee (north east Wales).
The Chirk Aqueduct
The Chirk Aqueduct carries the canal across the Ceiriog Valley to the south-west of Chirk. A cast iron trough is supported by 10 curved stone arches, carried on piers 65ft high. It was the first of the Welsh aqueducts to be constructed and, crucially, linked the coalfields, granite quarries and slate mines in the Ceiriog valley.