This is a cello band from Finland. From Wikipedia:
Apocalyptica is a heavy metal band from Helsinki, Finland, formed in 1993. The band is composed of classically trained cellists Eicca Toppinen, Paavo Lötjönen, and Perttu Kivilaakso (all three of whom are graduates of the Sibelius Academy in Helsinki) and drummer Mikko Sirén. Originally a Metallica tribute band, their music borrows elements from many genres including classical music, neo-classical metal, progressive metal, thrash metal, and symphonic metal. They have sold over three million albums to date.