There is no single word to define the diversity of ramen in current Tokyo. At this point in time, soy sauce ramen is known to have originated from the shop "Rai Rai Ken" in Asakusa in 1910. During postwar period, the thick noodles of "Ogikubo ramen", "Hope Ken" and dipping noodles started by "Taishoken" added variety to existing ramen. At the same time, these shops from all regions began to open and compete with the local ones in Tokyo. As such, the standard of ramen in Tokyo is going to be significantly raised in the future.
information source: GURUTABI