Glamorgan canalThere were 52 locks between Mertyr and Cardiff
Monmouth Canalthrough beech trees , 40 kilometer stretch without locks, longest in Britain.
Llangollen CanalChirk Aqueduct, dating from 1801, carries the canal about 20 meters above the River Dee. It is a precursor, in a way, of the later (only by two or three years) Pontcysyllte Aqueduct. It is a matter of conjecture whether these two viaducts should be attributed to William Jessop or Thomas Telford (or both).
To the right, you can see the later railway viaduct of 1848.
Continuing to the bottom of the picture, the canal boat would soon enter a 400 meter long
which comes out adjacent to Chirk railway station, although at a much lower level.
The Pontcysyllte aqueduct has an overall length of 307 meters and a maximum height above the Dee of 39 meters.
Ironically, the canal comes to a dead end on the other side of the aqueduct, apart from a feeder
to Llangollen, leading eventually to the Horsehoe Falls on the River Dee. The terrain northwards appears to have been the
main problem stopping the canal extending northwards as intended.