Please answer a question about the following article about Galicia (Spain):

Later the Muslims invaded Spain (711), but the Arabs and Moors never managed to have any real control over Galicia, which was later incorporated into the expanding Christian Kingdom of Asturias, usually known as Gallaecia or Galicia (Yillīqiya and Galīsiya) by Muslim Chroniclers, as well as by many European contemporaries. This era consolidated Galicia as a Christian society which spoke a Romance language. During the next century Galician noblemen took northern Portugal, conquering Coimbra in 871, thus freeing what were considered the southernmost city of ancient Galicia.

Ancient Galicians took control of which city in northern Portugal?
Coimbra