recknockshire Beacons or
Vans (often called the Beacons simply), the highest point of which, Pen
y Fan, formerly also known as Cadair Arthur, or Arthur's Chair, attains
an altitude of 2910 ft. In the north, a range of barren hills, which
goes by the general designation of Mynydd Eppynt (a name more properly
limited to its central portion), stretches right across the county in a
north-easterly direction, beginning with Mynydd Bwlch-y-Groes on the
boundary to the east of Llandovery, and terminating near Builth. In the
dreary country still farther north there is a series of rounded hills
covered with peat and mosses, the chief feature being Drygarn Fawr (2115
ft.) on the confines of Cardiganshire.

Of the valleys, the most distinguished for beauty is that of the Usk,
stretching from east to west and dividing the county into two nearly
equal portions. 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. The hilly country
to the north of the Eppynt is mainly drained by the Irfon, which falls
into the Wye near Builth. The Usk rises in the Carmarthenshire Van on
the west, and flowing in a direction nearly due east through the centre
of the county, collects the water from the range of the Beacons in the
south, and from the Eppynt range in the north by means of numerous
smaller streams, of which the Tarell and the Honddu (which join it at
Brecon) are the most important, and it enters Monmouthshire near
Abergavenny. The Taff, the Nedd (with its tributaries the Hepste and
the Mellte) and the Tawe, all rise on the south of the Beacon range and
passing through Glamorganshire, flow into the Bristol Channel, the upper
reaches of the Nedd and its tributaries in the Vale of Neath being
deservedly famous for its scenery. The mountains of the county
constitute one of the best water-producing areas in Wales. Recognizing
this, the corporation of Birmingham, under an act of 1892, acquired the
watershed of the Elan and Claerwen, and constructed on the Elan three
impounding reservoirs whence the water is conducted through an aqueduct
to Birmingham (q.v.). Swansea obtains its chief supply from a reservoir
of one thousand