The Welsh town of Caernarfon played a crucial role in the fraught history between England and Wales; here, in the late 13th century, English king Edward I built an imposing castle to solidify his conquest of the region. Recently, during a survey ahead of construction, archaeologists stumbled upon several important relics from Caernarfon’s medieval past—including possible remnants of the town walls that surrounded Edward I’s castle.

According to Arron Evans of the North Wales Chronicle, the C.R. Archaeology firm carried out its survey at Porth yr Aur, or “Golden Gate,” which was once the main seaward entrance to the borough adjacent to Caernarfon Castle. The area is now owned by a local “social enterprise” that plans to build a community health center there.

One of the key discoveries unearthed at the site was a flight of steps. As archaeologist Matthew Jones tells North Wales Live’s Amelia Shaw, the find is “very exciting” because it “could represent the remains of the original town wall, which was … built over in the 14th century.”

In the Middle Ages, according to the BBC, Welsh princes were vassals of the English king, but in the late 13th century, Prince Llywelyn ap Gruffudd—who had tussled with Edward’s father, Henry III—refused the English king’s summons to pay him public homage. Edward stormed into Gwynedd, the seat of Llywelyn’s power, and forced the prince into submission. Llywelyn’s geographic influence was greatly restricted, and after he began leading an uprising against the English crown in 1282, he was killed in a skirmish.

During his campaign in Wales, Edward set about building what became known as the “Iron Ring of Castles”—a series of towering fortifications meant to ward off and exert dominance over the disgruntled Welsh. In Caernarfon, Edward overhauled a manor that had been established by Welsh princes, building a castle he hoped would echo the intimidating walls of Constantinople. Next to the castle, he constructed a walled borough with a grid of streets, which, according to Encyclopedia Britannica, was anointed the capital of North Wales.

The town walls were built over in the 14th century; they had either been weakened by Welsh rebel attacks in 1297 or a fire in 1326, explains Jones to North Wales Live. The newly uncovered steps appear to belong to the original structure, making them a particularly special find. But the archaeological survey unearthed other treasures, too, including fragments of medieval pottery, among them the handle of a green wine jug associated with Saintonge ware. This style of pottery has been manufactured in the Saintes region of western France since the 13th century—a fact that, in turn, points to Edwardian Caernarfon’s international trade links.

Another “really interesting” find, according to Jones, was the remnants of what appears to be a doorway or a fireplace. If a doorway, the discovery could represent a previously unknown entrance to Caernarfon’s gate house, a building that controlled access to the town. A fireplace might give archaeologists a better sense of daily activities that took place during Caernarfon’s medieval period—something that experts are keen to know more about.

“We have maps that show buildings and some records of names of people who lived there,” says Jones, “but very little evidence of their day-to-day lives.”