Born in
Siena, Mariani graduated in
architecture at the
Accademia di Belle Arti di Roma, where he was a pupil of
Giuseppe Partini. He designed numerous buildings in his native Siena, and contributed to the restoration and renovation of ancient palaces and churches in the old town, including the
Rozzi Theatre (1894),
San Mamiliano in Valli (1896), the
Basilica of San Francesco (1903),
Santa Maria della Scala (1905–09),
Palazzo Salimbeni (1911–16) and the expansion of the San Niccolò Psychiatric Hospital (1914). In
Grosseto, Mariani designed the
Bastiani Grand Hotel (1910–12), the local headquarters of
Monte dei Paschi (1912) and the
Government Palace (1923–27). He also designed the Post Office Palaces in Siena (1908–12) and in
Messina,
Sicily (1912–14). He designed the city master plan of Siena in 1931. ==References==