Castles and Town Walls of King Edward in Gwynedd

The Castles and Town Walls of King Edward in Gwynedd is a World Heritage Site recognised by UNESCO. It is located in Gwynedd, Wales. The site includes the castles of Beaumaris and Harlech. It also includes the castles and town walls of Caernarfon and Conwy. It is considered to be the "finest examples of late 13th century and early 14th century military architecture in Europe".
History.
For the 20th century, the castles and walls were mainly known for their military purpose. It is described as the "zenith of English castle-building" by D. J. Cathcart King. It is because of the use of concentric defences, barbicans, and substantial gatehouses. Also, Sidney Toy considers them as "some of the most powerful castles of any age or country". 
In the late 20th and 21st centuries, historians such as Michael Prestwich and Abigail Wheatley both appreciate its roles as palaces and symbols of royal power. 
The location of the castles in Caernarfon and Conwy were chosen for their political significance and their military uses. The castles include luxury apartments and gardens. Caernarfon's castle and town walls had expensive stonework. They were perhaps made to suggest images of Arthurian or Roman imperial power. They are believed to have been made to improve Edward's personal prestige. 
The exact role of the royal architect James of St George in the construction is still being argued by many academics. The same with the influence of his native county of Savoy on the designs. However, the main sources indicate that he played a key role in its construction. They even described him as: “Magistro Jacobo de sancto Georgio, Magistro operacionum Regis in Wallia”. It means “Master James of Saint George, Master of the King’s Works in Wales.”
Recognition.
In 1986 sites were collectively announced a UNESCO World Heritage site. Together, they were called the "Castles and Town Walls of King Edward in Gwynedd". 
UNESCO considered the sites to be the "finest examples of late 13th century and early 14th century military architecture in Europe". UNESCO also brings up the importance of their links to Edward I and James of St George, their scale and advanced military architecture, and their unusually good condition and historical documentation. 
Maintenance costs.
The estimated costs to maintain the sites is around £239,500 during 2002–03. "Buffer zones" have been established around the sites. They are aimed to protect the views and setting from inappropriate development or harm. The sites are protected by a mixture of UK Scheduled Monument, Listed Building and conservation area legislation.