Sforzesco Castle.
Historical background
Along with the Cathedral - Milan's most famous and much beloved monument - the big Castle is linked to the vicissitudes and dramatic events that the city has been experiencing over the past centuries. For many years, in fact, it has represented a symbol of the power in the hands of the Dukes, as well as of the foreign dominators. Only at the beginning of the 20th century the Castle assumed its distinctive role, becoming a place of culture, which hosted numerous Lombard art collections. The Castle was named after Francesco Sforza, who transformed it into a ducal residence in 1450. But its origins date back to the second half of the 14th century, at the time of Galeazzo II Visconti.
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Sforza Castle is one of the symbols of Milan together with the Madonnina and the Galleria Vittorio Emanuele II. Built within ten years between 1358 and 1368 under Galeazzo II Visconti. The Castle was partly destroyed in 1447 because of a decision of the Ambrosia Republic, it was rebuilt during Francesco Sforza’s period.

Very nice, well thought/organized place with exhibitions, park, bars, places to relax. Always green, beautiful litte ponds with fish, most trees of Europ represented in the pack Sempione.

NIce old castle, n Nice park, but be aware from people that offering unuseful things

worth visiting if you're in MIlan