Sacrario della Milizia is an earlier 20th century Fascist-era military chapel at Viale Romania 45 in the Parioli quarter.
The chapel is part of the former Comando Generale della Milizia, which was the headquarters of the Milizia volontaria per la sicurezza nazionale which are better known in English as the Blackshirts.
The large complex was inaugurated by Mussolini on October 28 1936. The chapel was intended as a shrine to those Blackshirts killed in war service -they did actually fight in colonial campaigns in Libya and Ethiopia alongside the regular Italian army.
After the Blackshirts were suppressed in 1943, the complex became the Rome headquarters of the Carabinieri. It is now the Comando Militare della Capitale. As such, the chapel is under the care of the Military Ordinariate of Italy. There has been a recent restoration, including of the original mosaics by Vittoro Cafiero and Angelo Canevari.
You can't miss this one if you're in the vicinity. The complex is in the usual vaguely neo-Classical monumental style that the Fascists favoured, but the chapel is a unique tower on an ovoid plan. The fabric is in cubical blocks of brown tufo stone set in very thick mortar, with the blocks protruding and left rough (the style is called rusticated) so as to give a grim chequerboard effect. The street frontage has a total of 162 small square windows, each formed by replacing a block. The windows are in three grids, one above the other, with 54 windows in each grid (nine horizontally, six vertically).
The roof is flat, with a deep white parapet.
The interior is apparently a spectacular void, with enormous mosaics, but online depictions are lacking.
This building provides an enjoyable contrast with the more traditionally monumental Cappella dell'Istituto Pio XII delle Religiose dell'Assunzione across the street.