Born in 1884 in Milan, Italy, Colombo studied architecture in the Brera Academy under Giuseppe Sommaruga, the city's leading exponent of the Art Nouveau style.
Soon after his arrival in Buenos Aires he became director of a studio and later set up his own, working mainly on projects for private clients, usually wealthy Italian immigrants in business, industry or real estate who bought land for the construction of apartment buildings and shops for rental.
Colombo embraced Eclectic Modernism, used by many Italian architects working in Buenos Aires at that time, and typified by elements of Medieval architecture including the presence of round arches, windows and loggias, floral ornamentation and crenelated cornices.
To these traditional features were added those inspired by Art Nouveau and through exploring the possibilities offered by this combination Colombo was able to evolve a very personal language.
The first extends up to 1920 and falls within the Italian school of Art Nouveau, as exemplified by the headquarters of the Unione Operai Italiani at 1374-82 Sarmiento, completed in 1913.