Sincil Drain is a watercourse located in Lincoln, England. It flows through the city and eventually joins the River Witham. Historically, it has played a significant role in managing local drainage and preventing flooding in the surrounding areas. The drain is also known for its ecological importance, providing a habitat for various wildlife species. It is part of the broader Lincolnshire landscape and contributes to the region's natural beauty, making it a point of interest for both locals and visitors.