A fairly deep 380 metre, 8-10 metres deep canal cutting that starts some 40 metres north of Bridge 27 (Irish bridge) and reaches almost as far south as 26 (Whitehouse bridge). This is important for being a part of one of the first civil-engineering cut and fill schemes - spoil from this cutting being taken by construction railway or boated to form the huge embankment that was built at the south end of the Pontcysyllte Aqueduct in the period 1795-1801. Irish Bridge is a standard Telford/Jessop arched overbridge but supported on high abutments over the cutting.

The Ellesmere Canal Act was passed in 1793 and construction of the Chirk and Pontcysyllte Aqueducts began in 1795 with the canal open north to Froncysyllte in 1801 and south to the bottom of Frankton Locks in 1802. In 1813 the Canal became part of the Ellesmere and Chester Canal Company's property and in 1846 it became part of the Shropshire Union Railways and Canal Company but the following year was taken over by the LNWR. Transport on the canal diminished in later C19 with the arrival of the railways and then ceased by 2nd World War. The canal was only kept open because of its importance as a supplier of water.

INW 4-2007 and Stephen R. Hughes 25.05.2007.