GATE: Where the JSDF Fought

On a certain summer day in the year 20XX, in broad daylight a gate to another world appears in Ginza, Tokyo. An army and a swarm of monsters come storming through the gate. The Japan Ground Self-Defense Force is able to defeat the invaders and they head through the gate into uncharted lands. An epic fantasy about a battle between the human race and another world filled with dangerous enemies and beasts! *Source: Alpha Manga*