In the twentieth century, various mergers joined the castle town with neighboring Dōgo, Mitsuhama, and other townships, aided by urban sprawl, creating a seamless modern city that now ranks as the largest in Shikoku.As of the most recent merger, on January 1, 2005, absorbing the city of Hōjō, and town of Nakajima (from the former Onsen District), the city had an estimated population of 512,982 and a population density of 1,196 persons per km². Matsuyama is home to several universities including Ehime University (part of the Japanese national university system) and several private colleges, including Matsuyama University and Matsuyama Shinonome College. The Museum of Art, Ehime is the city's main art museum, its collections emphasizing the works of regional artists.
Also, hydrofoil service exists between Hiroshima and a few other destinations.Miura (boiler manufacturer), Iseki (tractor and engine equipment), Hatada Ichiroku (Japanese style confectionery), Poem, a food processing division of Pom (Ehime Drink Company), and the retailing companies Fuji and Daiki all have their headquarters in Matsuyama.The Matsuyama Declaration of 1999 proposed the formation of International Haiku Research Center, and the first Masaoka Shiki International Haiku Awards were given in 2000.Recipients have included Yves Bonnefoy (2000), Cor van den Heuvel (2002) and Gary Snyder (2004).This year's live action film on the hit anime "Death Note" will have Kenichi Matsuyama back as the legendary detective L, eight years after first playing the role in the 2008 film "L Change the World".
Crunchyroll reported that the 31 year old actor's L will have a brief appearance in the upcoming "Death Note Light up the NEW world".
Matsuyama also figures in several works by Shiba Ryōtarō, notably his popular novel, Saka no ue no kumo [Clouds Above the Hill] (1969).
In anticipation of the upcoming NHK Taiga drama adaptation of Saka no ue no kumo, a Saka no ue no kumo Museum was established in 2007.
It is located on the northeastern portion of the Dōgo Plain. Matsuyama was in medieval times part of the Iyo-Matsuyama Domain, a fiefdom of Iyo Province consisting mainly of a castle town, supporting Matsuyama Castle.
The city is known for its hot springs (onsen), among the oldest in Japan, and is home to the Dōgo Onsen Honkan, a Meiji Period wooden public bathhouse dating from 1894.
Iyo Railway also operates a system of trams and busses, which serve as the city's main modes of public transportation.