PHOENIX — A renowned home in northern Arizona and a famed castle that sits on South Mountain were recently listed as two of the nation’s most endangered historic places.

The two historical sites are the May Hicks Curtis House in Flagstaff and the Mystery Castle in south Phoenix.

The significant spots each took a place on the 2025 list of America’s 11 most endangered historic places, which is put out by the National Trust for Preservation.

Details on two endangered Arizona historic places

The Flagstaff location was the former home of May Hicks Curtis House known as the Betsy Ross of Arizona. Curtis stitched together the first Arizona state flag in 1911.

She lived and worked at the home for decades. The home is endangered because it was slated for demolition for private land development, according to state officials. 

The city of Flagstaff acquired the home and hopes to save the historical site by relocating and restoring it. Curtis was considered a pioneer who dedicated her life to helping her community.

Arizona Secretary of State Adrian Fontes has spoken out in favor of preserving the home.

“As America’s 250th birthday approaches, let us remember the May Hicks home, now listed among America’s Most Endangered Historic Places,” Adrian Fontes said in a Wednesday city of Flagstaff release.

“Saving places like hers keeps alive the frontier spirit that built both the state of Arizona and the nation itself.”

The second Arizona historical spot to make the national list was the Mystery Castle that was built by hand and with lots of love. The castle was constructed by Boyce Luther Gulley between 1934-1945 for his daughter Mary Lou.

The castle is located at 800 E. Mineral Road, south of Baseline Road and Seventh Street.

Gulley had no formal architectural or engineering training and built the castle without plans or permits.

Mary Lou and her mother opened the Mystery Castle to the public and made it a tourist attraction.

In 2022, the tours were suspended due to vandalism and summer storms.

The castle has been unoccupied for years and is considered endangered because it needs funding to stop it from deteriorating to have it reopened to the public.

Why is there a list for endangered historic places?

For nearly 40 years, the National Trust for Preservation has created its annual list of historic endangered places to raise public awareness on important cultural landmarks. The list has helped garner public support and helped save 350 endangered sites with only a few lost.

“Across the United States, compelling, meaningful historic sites are at risk, whether from natural disasters, underutilization, neglect or lack of awareness. Each site on this year’s list has inspired passionate supporters from their surrounding communities to work together to save these cherished landmarks and repurpose them for the public, now and into the future,” Carol Quillen, president and CEO of the National Trust for Historic Preservation said in a Wednesday release.

“Their leadership shows the power of preservation to create stronger communities, energized local economies and a healthier environment for everyone.”