Fourteen miles north of Newport, the valley of the Llwyd opens out at the airy iron and coal town of BLAENAFON (sometimes Blaenavon), whose population has shrunk to five thousand, a quarter of its nineteenth-century size. It's a fascinating and evocative place, a fact recognized by UNESCO, who granted it World Heritage Site status in 2000. The town's boom kicked off at the Blaenafon ironworks , just off the Brynmawr road (April-Oct daily 9.30am-4.30pm; call 01633/648081 for winter hours; £2; CADW), founded in 1788. Limestone, coal and iron ore - ingredients for successful iron-smelting - were abundant locally, and the Blaenafon works grew to become one of the largest in Britain in the early nineteenth century, until it closed in 1900. The line of Georgian blast furnaces, the water-balance lift and the museum in the workers' cottages offer a thorough picture of both the process and the lifestyle that went with it. The ironworks also contains the town's tourist office (same hours; tel 01495/792615).

Just as it is now possible to visit the home of Blaenafon's iron industry, the town's defunct coal trade has also been transformed smoothly into the site which most clearly evokes the experience of a miner's work and life. At the Big Pit National Mining Museum (mid-Feb to Nov daily 9.30am-5pm; last underground tour 3.30pm; free), a mile west of the town and reached by a half-hourly shuttle bus from Blaenafon, you're kitted out with lamp, helmet and very heavy battery pack and lowered three hundred feet into the labyrinth of shafts and coal faces for a guided tour. The guides - most of whom are ex-miners - lead you through explanations and examples of the different types of coal mining, from the antiquated, risky stack-and-pillar operation to modern, mechanized seam-working. Constant streams of rust-coloured water flow by, adding to the dank and chilly atmosphere that must have terrified the small children who were once paid twopence for a six-day week - of which one penny was taken out for the cost of their candles - pulling the coal wagons along the tracks. Back on the surface, the old pithead baths, smithy, miners' canteen and winding engine house have all been preserved and filled with some fascinating displays about the local mining industry, including a series of characteristically feisty testimonies from the miners made redundant here in 1980.