were there any archaeological discoveries made at the second last place?
Yes, at Glac, a palace is being excavated
Sirmium
At Glac near Sirmium a palace is being excavated, indicated by the luxurious construction materials coming from all over the Mediterranean, such as red and green porphyry from Egypt and the Peloponnese, and marble from Tunisia, Greece and Italy. 
what was the capitol of the roman empire Constantinople what led to the empire's fall? The death of Nepos and abolition of the Western Empire by Zeno what crisis did it face in the third century? After assassination of Alexander Severus, the Roman Empire sank into a 50-year period of civil war was there any need for the restoration? Yes what does tetrarchy as per the empire mean? This system effectively divided the Empire into four major regions, as a way to avoid the civil unrest that had marked the 3rd century. what were the names of the regions ? Mediolanum, Trier, Sirmium and Nicomedia.
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Sirmium [SEP] Archeological findings
At Glac near Sirmium a palace is being excavated, indicated by the luxurious construction materials coming from all over the Mediterranean, such as red and green porphyry from Egypt and the Peloponnese, and marble from Tunisia, Greece and Italy. Some say it is that of Emperor Maximian and according to Aurelius Victor built on the place where his parents worked as labourers on the estate. During the construction of the hospital in 1971, more than eighty altars were found in a monumental sanctuary to Jupiter, which is the second largest in Europe. Sirmium had two bridges with which bridged the river Sava, Ad Basanti and Artemida's bridges according to historical sources.