Trondheim
From Tardis Wiki, the free Doctor Who reference
Trondheim was a city located on the north-east coast of Norway. (TV: The Lie of the Land) It was across the Atlantic Ocean from Iceland. (PROSE: Dark Horizons)
In the 12th century, it was ruled by Duke Wolvern, who had united the warring tribes, brought peace to the region and established trading with their neighbours. A Viking longship arrived at Trondheim and picked up Princess Freydis for transport to Iceland. (PROSE: Dark Horizons)
"Trondhe" was one of the many locations that could be seen on the map that Nardole showed Bill. (TV: The Lie of the Land)