Castello dell’Innominato ('the unnamed castle') history dates back to the Carolingian period. At that time on the hill of Somasca, the upper district of Vercurago, there was a signalling tower, that became a fortress some centuries later (documented in 1158). From 1454 this land felt into the clutches of the Republic of Venice and the Adda River became the natural border between the Serenissima (Venice) and the duchy of Milan.The fortress was destroyed by the French, who begun some months before a war against Venice and the bailey was shelled by the Russian in 1799 during the battle between the Napoleonic troops and the Austro-Russian.
today the stone arch, small chapel and walls remain. From the bailey you can admire the wonderful landscapes and sights on the eastern branch of Lake Como to the Alps (north) and the flow of the Adda River (south).
References:The Church of St Donatus name refers to Donatus of Zadar, who began construction on this church in the 9th century and ended it on the northeastern part of the Roman forum. It is the largest Pre-Romanesque building in Croatia.
The beginning of the building of the church was placed to the second half of the 8th century, and it is supposed to have been completed in the 9th century. The Zadar bishop and diplomat Donat (8th and 9th centuries) is credited with the building of the church. He led the representations of the Dalmatian cities to Constantinople and Charles the Great, which is why this church bears slight resemblance to Charlemagne's court chapels, especially the one in Aachen, and also to the Basilica of San Vitale in Ravenna. It belongs to the Pre-Romanesque architectural period.
The circular church, formerly domed, is 27 m high and is characterised by simplicity and technical primitivism.