Conwy was founded by the English king Edward I in 1283 as one of a chain of fortified towns in the then newly invaded North Wales. A Cistercian monastery already occupied this site; but Edward removed the monastery upstream to Maenan, leaving its church as the borough's parish church. Edward built a castle, a town, and walls to surround them both. The town was built on a grid plan as nearly as the site permitted, with the castle on the riverbank in the southeast corner. The castle is roughly rectangular, with eight round towers, each 40 feet (12 metres) in diameter, along its sides. The town walls themselves are fortified with 21 towers and have 3 gateways. Though the castle was partially dismantled in 1665, the town walls have remained virtually complete, making Conwy one of Europe's finest surviving examples of a medieval bastide (a town laid out according to a definite geometric plan). Sixteenth-century buildings in the town include the mansion Aberconwy (c. 1500), Plâs Mawr (the “Great House,” built in 1577–80, now housing the Royal Cambrian Academy of Art), and the Black Lion (1582; a coaching inn). Deganwy, across the Conwy estuary, is of much greater antiquity, with a 6th-century Welsh fortress, but little remains of its fortifications, and after Conwy was founded it became subordinate to the new town.

The deeply indented estuary of the River Conwy has long been an obstacle to travelers along the coast of northern Wales. The Scottish engineer Thomas Telford (Telford, Thomas) designed the first bridge across the estuary at Conwy; the roadway of his innovative Conwy Suspension Bridge (1822–26) is suspended from huge wrought-iron chains. To carry a rail line across the estuary, the English engineer Robert Stephenson (Stephenson, Robert) completed a tubular iron-and-steel bridge at Conwy in 1848. A modern road bridge was completed alongside these two bridges more than a century later (1958), but it proved insufficient to accommodate the growing automotive traffic along North Wales's coastal highway. In 1990 a concrete road tunnel was completed beneath the Conwy estuary's channel to bypass the town of Conwy with much of this traffic. Conwy is now primarily a tourist centre. It is also the administrative centre of Conwy county borough. Pop. (2001) 14,208.

county borough, northwestern Wales, along the Irish Sea. Conwy's coast includes the rugged headlands of Penmaenmawr and Great Orme's Head along with a low-lying strip reaching east to the mouth of the River Clwyd. From the coast the county borough extends inland along both sides of the River Conwy to the mountains of Snowdonia. The area west of the River Conwy and a small enclave east of the river below Llanrwst lie within the historic county of Caernarvonshire (Sir Gaernarfon). The portion of Conwy to the east of this area belongs to the historic county of Denbighshire (Sir Ddinbych).

Most of the county borough's population is concentrated along its coastal strip, where tourism is the main industry. Colwyn Bay is one of the most popular seaside resorts and the largest town. The town of Abergele, located east of Colwyn Bay, was one of the first places in North Wales where “sea bathing” became popular. It is now a thriving market centre with weekly cattle markets. The coastal resorts of Conwy, Penmaenmawr, Llanfairfechan, and Llandudno all have lengthy sand beaches. The stone statue of a rabbit checking its watch, located on the western promenade of Llandudno, commemorates the part the town played in inspiring Lewis Carroll (Carroll, Lewis)'s Alice's Adventures in Wonderland (1865).