Q:River Swilly - The River Swilly (Irish: An tSuileach) is a river in Ireland which flows in an eastern direction through Letterkenny County Donegal. Letterkenny the largest town in County Donegal is built on the river and became the first crossing point on the river in the 17th century. Given a choice of categories company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work, the text refers to which one?
A:
Natural Place