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In page Leeuwarden:

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The oldest remains of houses date back to the 2nd century AD in the Roman era and were discovered during an excavation near the Oldehove. Inhabited continuously since the 10th century, the city's first reference as a population centre is in German sources from 1285, and records exist of city privileges granted in 1435.[citation needed] Situated along the Middelzee, it was an active centre of maritime trade.[1] The waterway silted-up in the 13th century.[2]