Florence is a coastal city in Lane County, in the U.S. state of Oregon. It lies at the mouth of the Siuslaw River on the Pacific Ocean and abou…Florence is a coastal city in Lane County, in the U.S. state of Oregon. It lies at the mouth of the Siuslaw River on the Pacific Ocean and about midway between Newport to the north and Coos Bay to the south along U.S. Route 101. As of August 14, 2023, the city had a total population of 9,553.