|13, 58.5378, 44.8650|
|Tircambran (88%), Other (12%)|
|Nationalities||Tircambran (94%), Other (6%)|
|• Mayor||Tomos ap Tomos Siân|
|• Estimate (2015)||238,382|
|• Census (2012)||237,044|
The City of Porthbrenin (Dinas Porthbrenin) is situated on the southern coast of Tircambry. It is the capital of the province of Rhysiog and chief town of Cantref Donllanion. It was incorporated as a city in 1762 through the merger of the City of Aberffenwy and town of Llanddewi, along with some surrounding area. Its borders have expanded since then and it now occupies and area of XXX sq.km., with a population of 238,382.
The name Porthbrenin is taken from the bay around which the city is situated. The name means "King's Harbour", a name which was adopted in 1299, after the Duke of Rhysiog assumed the title of King. Prior to that the bay had been called Porthdug ("Duke's Harbour") since c.1218, and before that Bae Gwyrdd ("Green Bay") after the main river which flows into it. The name Porthdug was adopted to emphasise the ownership of the Duke of Rhysiog in response to a growing and increasingly assertive Wesman presence in the area.
There has been a settlement at the mouth of the Ffenwy River, on the north side of Porthbrenin Bay, since ancient times, and other settlements around it since at least the early Middle Era, the most significant of which was the religious settlement of Llanddewi on the southeast of the bay.
In the early Middle Era, Aberffenwy was little more a fishing village within the Estate (Ystad) of Cwmfeliog, but it grew into a small trading port and then came to prominence in the twelfth century when High Lord Caradog I of Rhysiog based himself in the area, at Penmaion just to the west of the town. For thirty years in the early thirteenth century a contingent of Knight Venturers, under the leadership of Sir Kenneth of Inverbervy, were based in Aberffenwy, and their compound went on to become Palas Unferberfi, the chief royal palace of the Kingdom of Rhysiog.
In the fourteenth century Aberffenwy became home to the new Parliament of Rhysiog, and, on the other side of the Ffenwy River, Porthbrenin University was founded. The city flourished during the 16th century, but began to lose prominence after 1641 because Rhysiog's new monarch, Queen Bronwen, lived with her husband in Caerarthen rather than in her capital city. Aberffenwy's political importance diminished even more after 1671, when Morionys and Rhysiog were formally united as a single kingdom, with its capital in Caerarthen.
Throughout its history as a city, Aberffenwy was a major trading port. It joined the Vinnic League in 1274, and operated a system of exclusive trading guilds.
Across the water, Llanddewi began as a village supporting the monastic community of St.David's Abbey (Abaty Sant Dewi), until the abbey was destroyed by royal troops 1441 after the monks had been plotting against the king in the Fifty Years War. It was also a trading port, and there was a longstanding and sometimes bitter rivalry with Aberffenwy. In a bid to end the rivalry, Parliament forced the city and town to merge in 1762, creating the new City of Porthbrenin under a single Corporation.
The new city entered the industrial age with the benefit of a new wetwater dock, Doc Gareth, which opened in 1764 on the south side of the bay, and later with the establishment of the De Llegar Copperworks on the east bank of the Gwyrdd River.