Milford's Promont House Museum will open for free public tours on Sept. 19 as part of a countywide America 250 celebration.

The open house takes place at the 1865 Victorian mansion at 906 Main St. It is one of 21 Clermont County museums and historic sites participating in the coordinated event, according to the Greater Milford Area Historical Society. Regular admission runs $8 for adults, $3 for students 13 and up and free for children 12 and under accompanied by a member or paying adult. On Sept. 19, everyone gets in free.

The museum's event page lists hours as 10 a.m. to 2 p.m., while the historical society's main website lists the open house running from 10 a.m. to 4 p.m. Visitors can confirm hours by calling (513) 248-0324 or emailing [email protected].

Promont was once the home of John M. Pattison, the 43rd governor of Ohio. The Italianate-style mansion still stands in its original form, with a central hall flanked by connecting rooms across four floors. The grounds once spanned 56 acres reaching the historic Five Points intersection. The name "Promont" comes from Latin, meaning a prominent mass of land overlooking lower ground. William George Williams, a professor at Ohio Wesleyan University and Pattison's father-in-law, chose the name.

The Sept. 19 event ties into the Clermont County History & Museum Passport, a program funded by a $5,000 America 250 Ohio grant to the Clermont County Convention and Visitors Bureau. The passport was created in partnership with 15 museums across the county. Visitors collect stamps at participating sites, covering early settlement stories, aviation history, agriculture and the legacy of President Ulysses S. Grant.

Participating Museum Day organizations span the county, including the Loveland Historical Society & Museum, Clermont County Historical Society, Grant Boyhood Home Association and Chilo Lock #34 Park & River Museum.

The Greater Milford Area Historical Society, established in 1967, operates Promont and maintains a reference library and gift shop on site. Upcoming events at the museum include Art Affaire on Sept. 26 from 11 a.m. to 5 p.m. and a Holiday Tea on Saturday, Dec. 12. Regular public tours resume on the first, third and fifth Sundays of each month, with the next dates on Oct. 4 and Oct. 18.