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Limestone relief from Ragasch near Philippopolis, Thracia, cited in MMM without further details.
Small arched marble tauroctony relief from Philippovtsi near Sofia, Thracia, divided into two parts by a horizontal rim.
This Mithraic relief of the Danubian type was found in 1940 in the old town of Plovdiv.
The Mithraeum of Serdica was found in the fortified area of the ancient city of Serdica, now Sofia, Bulgaria.
This very fine relief of Mithras killing the bull was discovered in 2014 in Germán, near Sofia, Bulgaria, and is now housed in the Sofia History Museum.