Located in the Syndicate Block, East side of Nicollet Between 5th Street and 6th Street, (Razed).  The Syndicate Block was one of the most ambitious development projects of its day. It contained some five acres of office and retail space. Among the many tenants the Syndicate housed through its hundred-year history, there were two notable photography studios: the studio of Frederick E. Haynes, and the Sweet Studio. Both of these studios were located in suite 605.  Larry Millet, in his book Lost Twin Cities, describes the origin of the Syndicate Block: “In 1881 a dozen Minneapolis businessmen formed a syndicate, bought a choice lot on Nicollet Avenue for $77,500, and laid plans for a huge office and retail building. The Syndicate invited several leading architects -- including William Dennis, E. Townsend Mix, and Frederick Kees -- to submit plans. Kees, then in partnership with Burnham W. Fisk, won the competition, and work on the project began in 1882” (p. 156).  The Syndicate Block lasted for over one hundred years, but the exterior of the building went through various changes mostly because of fire damage and subsequent repair.
http://www.placeography.org/index.php/Syndicate_Block,_East_side_of_Nicollet_Between_5th_Street_and_6th_Street,_%28Razed

 http://reflections.mndigital.org/cdm/ref/collection/wch/id/242