Matsumoto Castle (Matsumoto-jō, also known as Crow Castle or Karasu-jo due to its black exterior) rates as one of Japan's Top Three Castles alongside Himeji and Kumamoto Castles and houses a comprehensive exhibit on the history of firearms in Japan. Given a lack of English language signage, that might not be such a big draw card, but Matsumoto is largely intact, unlike other sites that have been reconstructed in ferroconcrete.
It also differs in being flatland castle (hirajiro) built on a plain beside a swamp rather than on a hilltop or a river crossing. This lack of natural defences meant the castle ended up boasting three concentric moats and an extensive system of inter-connecting walls and gatehouses with an outer earthen wall almost around three kilometres in circumference designed to deaden cannon fire.
What you’re looking at today, however, is the five-tiered, six-storied main castle keep (tenshukaku) and smaller, secondary donjon, built from 1592 to 1614 as an upgrade to a previous fortification (Fukashi Castle) which dated back to 1504.