Join Lowell National Historical Park for Lowell Walks, a series of guided, 90-minute tours taking place throughout historic Lowell! Reservations are not required, and all tours are FREE. Tours begin at the NPS Visitor Center at 246 Market St. Please arrive 10 minutes before the tour starts. Dress for the weather and remember to bring water! Free parking is available at 350 Dutton St. in the Hamilton Canal Innovation District garage. This week: Mill Girl History with Lowell NHP Ranger Tess Shatzer. Explore downtown sites and learn about issues that were important in the daily lives of Lowell's 19th century "mill girls."