The three reservoirs on the Elan were completed in 1904.
He was present at the engagements of Hort and Hatvan, converted the doubtful fight of Tap16-Bicsk into a victory, and fought with irresistible elan at the bloody battle of Isaszeg.
Near Rhayader are the large reservoirs constructed (1895) by the corporation of Birmingham in the Elan and Claerwen valleys.
But the great reservoir known as Lake Vyrnwy, which supplies Liverpool with water, is equal in size to Bala; and the chain of four artificial lakes constructed by the Birmingham corporation in the valleys of the Elan and Claerwen covers a large area in west Radnorshire.
The Wye is the chief river, and forms the boundary between the county and Radnorshire on the north and north-east, from Rhayader to Hay, a distance of upwards of 20 m.; its tributary, the Elan, till it receives the Claerwen, and then the latter river, continue the boundary between the two counties on the north, while the Towy separates the county from Cardigan on the north-west.