Editor replies: Neville: The easiest route is from the car park at Storey Arms, on the A470 road, about an hour drive north from Cardiff, or 20 minutes south from Brecon. It's an easy ascent of only 500m or so up a busy track. A return trip would take between 2 and 3 hours. There are alternative routes from the north (starting at lower altitude, much longer, much more impressive, and with fewer people). Another alternative is to climb from the minor road between Merthyr and Talybont-on-Usk (a village that has excellent places to east and drink - notably The Star Inn). Even if there is only a light breeze in the car park, expect strong winds on the Corn-Ddu, Pen Y Fan summit ridge.