After abandoning the Alblimes (a Limes generally following the ridgeline of the Swabian Jura) around 150 AD, Aalen's territory became part of the Roman Empire, in direct vicinity of the then newly erected Rhaetian Limes. The Romans erected a castrum to house the cavalry unit Ala II Flavia milliaria; its remains are known today as Kastell Aalen. The site is west of today's town centre at the bottom of the Schillerhöhe hill. With about 1,000 horsemen and nearly as many grooms, it was the greatest fort of auxiliaries along the Rhaetian Limes. There were Civilian settlements adjacent along the south and the east. Around 260 AD, the Romans gave up the fort as they withdrew their presence in unoccupied Germania back to the Rhine and Danube rivers, and the Alamanni took over the region. Based on 3rd- and 4th-century coins found, the civilian settlement continued to exist for the time being. However, there is no evidence of continued civilization between the Roman era and the Middle Ages.
There is a Limes Museum located adjacent the Kastell.
References:The Jan Hus Memorial stands at one end of Old Town Square. The huge monument depicts victorious Hussite warriors and Protestants who were forced into exile 200 years after Hus, and a young mother who symbolises national rebirth. The monument was so large that the sculptor designed and built his own villa and studio where the work could be carried out. It was unveiled in 1915 to commemorate the 500th anniversary of Jan Hus' martyrdom. The memorial was designed by Ladislav Šaloun and paid for solely by public donations.
Born in 1369, Hus became an influential religious thinker, philosopher, and reformer in Prague. He was a key predecessor to the Protestant movement of the sixteenth century. In his works he criticized religious moral decay of the Catholic Church. Accordingly, the Czech patriot Hus believed that mass should be given in the vernacular, or local language, rather than in Latin. He was inspired by the teachings of John Wycliffe.