Società per Azioni Immobiliare Gallia di Milano, commonly known as Gallia, was an Italian real estate company based in Milan. Founded in 1871, Gallia played a significant role in the development and management of real estate properties in the city of Milan.

The history of Gallia is intertwined with the urban and real estate development of Milan throughout the 20th century. The company primarily focused on acquiring land, constructing residential and commercial buildings, and then managing and leasing the real estate properties.

During the years of Italy's economic boom in the 1950s and 1960s, Gallia engaged in large-scale real estate development projects, contributing to the expansion of the city. They built residential complexes, offices, hotels, and shopping centers that helped transform Milan into a major urban and financial center.

In the following years, Gallia continued to acquire and manage real estate properties, but the company faced challenges in the 1980s and 1990s when the real estate sector experienced an economic downturn. This led to a reduction in activities and a restructuring of the company.

Over the years, Gallia focused on maintaining and enhancing its real estate portfolio. However, the company gradually scaled back its operations and lost prominence in the Milan real estate sector.

Please note that the information provided is based on my knowledge up until September 2021, and there may have been further developments or updates regarding Società per Azioni Immobiliare Gallia di Milano since that time.