902 3rd Avenue
Landmark Designation: 1977
Construction Date: 1892
Architectural Style: Queen
W.B. Wiswall was a partner in a hardware business with J.B.
Thompson. He married Miss Hattie Atwood at the Congregational Church in
Longmont in 1876. In 1892, he was serving as secretary of the Longmont Electric
Light Co., and was also interested in the Inter-Ocean Mine above Boulder.
Hattie M. Denio became owner of the house in 1896. Hattie and her husband,
James Wilbur Denio, came to Longmont from New York in 1872. Mr. Denio worked
as a miller at Fox's St. Vrain Flouring Mill, but soon struck out for himself
and established the Longmont Flour Mill, also known as Denio-Barr Mill, which
burned down in 1934. Mr. Denio was active in the community and served as Trustee
for the town from 1883-1885 and again from 1893-1894.
A section of the Longmont Flour Mill property has been preserved as a park,
Old Mill Park
and is maintained by the St.
Vrain Historical Society.