Other sights in PowysPowys, Wales

Show cave complex in the upper Tawe valley with lit chambers, stalactites and an underground river.

Long-running eco visitor centre near Machynlleth in the Dyfi Biosphere, with displays on renewable energy and sustainable living.

The highest and most elaborate of the Elan Valley dams, its curving Victorian wall stepped with overflow arches.

Working farm near Rhayader with a daily red kite feed that draws hundreds of birds, watched from hides.

The highest road pass in Wales, threading between Hay Bluff and Twmpa above the Vale of Ewyas.

Steep scarp on the northern edge of the Black Mountains with wide views over the Wye valley.

Free visitor centre on Mynydd Illtud common at Libanus, with a cafe, sculpture garden and open views to the peaks.

Cave with the largest entrance in Wales, formed where the Afon Mellte vanishes underground near Ystradfellte.

Waymarked walk through Hafren Forest to the boggy source of Britain's longest river on the flank of Pumlumon.

Flat-topped hill above Crickhowell crowned by an Iron Age hillfort, giving the town its Welsh name.

Hilltop viewpoint and bronze figure on the Machynlleth-to-Llanidloes mountain road above Dylife, overlooking the Cambrian Mountains.