This postcard, postmarked 1907, shows a boat passing the Grand Avenue (now Wisconsin Avenue) Bascule bridge. (A bascule bridge is just a fancy name for a drawbridge).
This bridge would have been fairly new at the time this image was captured. A swing bridge, which pivoted horizontally from a piling in the center of the river, was replaced with this bridge in 1902. The old swing bridge was moved six blocks north to Chestnut Street, which is now called Juneau Avenue. In 1901, the city received four bids to build this bridge, ranging from $84,700 to $103,486 for an “ornamental structure.” (Those figures would be equal to $2.5M to $3.1M today.)
Just over the bow of the ship, you can see the J. C. Iversen building. John C. Iversen established his picture-framing business in 1867 on Spring Street (later Grand Avenue). The business prospered and expanded in 1879 to this five-story building you see here on E. Water Street (now N. Water Street).
On the left, you see the old four-story Gimbel’s building that was razed to make way for the new eight-story building in the 1920s. (At the top, you can see the last two letters of the Gimbel’s name.)
In the center is, of course, City Hall. To the right is the Pabst Building and Mack Block Building, across from each other on what is now Wisconsin Avenue.
I think the only thing visible in this image that still stands is city hall.
Sources:
https://www.milwaukeeriverkeeper.org/milwaukee-bridge-history/
http://bridgehunter.com/wi/milwaukee/B40048800000000/
https://milwaukeehistory.net/wp-content/uploads/2018/05/2008.J.C.-Iversen-Co.pdf
https://urbanmilwaukee.com/2015/06/16/yesterdays-milwaukee-j-c-iverson-co-about-1879/
Identifiers:
PLUS Code: 23PQ+XW Milwaukee, Wisconsin
Approximate Google Street View today: https://goo.gl/maps/d4twmHVXbdjWXVwM7
SS Christopher Columbus was the only whaleback ship ever built for passenger service. The ship was the longest whaleback ever built, and reportedly also the largest vessel on the Great Lakes when she was launched. She served as an excursion liner on the Great Lakes between 1893 and 1933 and began life shuttling visitors from downtown Chicago to the World’s Columbian Exposition. The ship could carry 4,000 to 5,000 passengers on her four decks, but it was reported that she carried 7,000 on her maiden voyage. She was scrapped in 1936.
Just beyond that is the Matthews Bros building. Matthews Bros. was considered one of Milwaukee’s most celebrated furniture manufacturers. It was founded by brothers Eschines and Alonzo Matthews. They moved from Ohio to Milwaukee in 1856 and occupied many addresses before arriving at this spot. In 1857, Matthews Bros was founded on East Water between Biddle and Martin (now known as Kilbourn and State). Three years later they moved to a new location on East Water between Biddle and Oneida (Kilbourn and Wells). In 1863, the brothers relocated to a store on the west side of this block on East Water. In 1870, the firm built 
The building on the right has signs for “Nase, Kraus & Koken,” a company that made wallpaper. This building was razed to make way for the 
