Milan used to be likened to Venice, because of its architecture and its canals, and – up until the XIX Century – it was ranked among the most beautiful cities in the world. The waters of the Adda rivers flowed through the networks of canals known as the Navigli, making it navigable. The Naviglio in Via San Marco, with the still visible Leonardo Lock (IV Cent.), regulated its flow. This museum was built as a testimony to the grandiosity of that structure. The historic relevance of its exhibition and the beauty of its halls (some of which date back to the middle-ages) this is considered one of the most important vestiges of ancient Milan. Located in the hip district of Brera, the museum welcomes visitors and offers guided tours, but it is also occasionally available for special events.