I visited the Chirk Aqueduct, the Chirk Tunnel, and the Pontcysyllte Aqueduct in May, 2016.
I took a train first from Chester (a beautiful city itself) to Chirk (where I had only 45 minutes between trains) to see the aqueduct and the tunnel. Then took a train back to Ruabon (where I had 2 hours between trains) to take a bus to Trevor to see the Pontcysyllte Aqueduct. And then took a bus back to Ruabon and a train back to Chester.
The photo 1 shows the Chirk Aqueduct. The photo 2 shows the Chirk Aqueduct for water and ship and the Chirk Viaduct for train. The photo 3 shows the Chirk Tunnel, where I came across a boat when I was walking through. The photo 4 shows the Pontcysyllte Aqueduct with 2 boats on it (although difficult to see in the photo).
Unfortunately, I didn't have time to visit the Horseshue Falls, where the Llangollen Canal starts off the River Dee.
I find it interesting that there are some people who live on the uniquely narrow boats on this canal.
I think there are terminology confusions in the "Brief Synthesis" and the "Map" at the UNESCO website. With the Brief Synthesis I believe the canal is called Llangollen Canal and not Pontcysyllte Canal. The bridge by Trevor is called Pontcysyllte Aqueduct. Pont means bridge anyway. The centerpiece of this WHS is the Pontcysyllte Aqueduct. The other tunnel, "Whitehouse Tunnel," used to appear as "Whitehurst Tunnel" on the Google Map, but now it seems to have been corrected as "Whitehouse Tunnel." The bus stop above this tunnel seems to be called "Whitehurst" bus stop.
Because the core zone of this WHS is some first length of the Llangollen Canal, I think the WHS should be called Llangollen Canal, or maybe Llangollen Canal with Pontcysyllte Aqueduct.