Machynlleth (pronounced [maˈχənɬɛθ] ⓘ) is a market town, community and electoral ward in Powys, Wales and within the historic boundaries of Montgomeryshire.

In the late 1990s, radiocarbon dating showed that copper was being mined in the Early Bronze Age (c. 2,750 years ago), within 1 mile (1.6 km) of the town centre.

[9] One of the earliest written references to Machynlleth is the Royal charter granted in 1291 by Edward I to Owen de la Pole, Lord of Powys.

According to local tradition, Dafydd Gam, a Welsh ally of the English kings, was imprisoned here from 1404 to 1412 for attempting to assassinate Owain Glyndŵr.

[citation needed] The weekly market and biannual fair thrived, and in 1613 drew complaints from other towns whose trading in cloth was being severely affected.

A document dated 1632[citation needed] shows that animals for sale came from all over Merionethshire, Montgomeryshire, Cardiganshire, Carmarthenshire and Denbighshire, and prospective buyers came from Flintshire, Radnorshire, Brecknockshire, Herefordshire and Shropshire, in addition to the above.

In 1846 Mary Cornelia, the daughter of a local landowner Sir John Edwards married Viscount Seaham, the second son of the third Marquess of Londonderry and they set up home at Plas Machynlleth.

To celebrate the 21st birthday of the Seahams’ eldest son, Viscount Castlereagh, the townspeople paid for the clock tower which stands at the town's main road intersection.

The clock tower, designed by Henry Kennedy of Bangor and now a Grade II listed monument, cost £800; the townspeople raised £1,000, of which the remainder was spent planting trees along nearby streets.

[14] Another son, Lord Herbert Vane-Tempest, was the last member of the family to live at the Plas and was killed in the Abermule train collision on the Cambrian Railways, of which he was a director.

Various local government re-organisations saw responsibility for the Plas pass first to Montgomeryshire District Council, who in 1995 converted it into the Celtica visitor centre.

With little scope for alternative investment, Celtica closed in March 2006, and the house stood empty while Powys County Council sought to relinquish responsibility for it in line with their policy of selling many of their publicly owned buildings.

[15] The town is home to the signalling centre that controls the European Rail Traffic Management System (ERTMS) on the Cambrian Line.

[18] Machynlleth has a special role in Welsh history because of its connection with Owain Glyndŵr, a Prince of Wales who rebelled against the English during the reign of King Henry IV.

The town has hosted the Machynlleth Comedy Festival annually since May 2010, featuring comedians such as Jon Richardson, Pappy's, Josie Long, Stewart Lee and Richard Herring.

[20] Lambert had previously tried to convert the town's old railway station into a hotel and museum, employing international architect Richard Rogers.

[21] Machynlleth is the home of Ecodyfi, a locally controlled organisation that was set up to foster and support a greener community and economy in the Dyfi Valley.