You can see what Prague looked like circa 1900 via prints in the U.S. Library of Congress. The color lithographs were sold as part of a set called "Views of the Austro-Hungarian Empire."
The original black-and-white photos had color added in a process called Photochrom, an early variation on colorization. The set was sold in the U.S. by the Detroit Publishing Company in 1906, but seems to have been printed in Switzerland by an oddly named company called Photoglob.
Places like the National Theater, National Museum, Charles Bridge, and entry to Prague Castle still look much the same, save for the fashion donned by some people.
Malostranské náměstí, though, has a statue of Marshal Josef Václav Radecký, which was taken down in 1919 and put into storage. Old Town Square sports the Victory Column that was town down in 1918 and recently replaced with a copy, as well as an older version of the face of the Astronomical Clock, which seems to be undergoing repairs as the inner wheel is missing.
The set includes the Legion Bridge (originally the Emperor Franz Bridge), which wasn’t built until 1901, which helps to narrow down the dates.