There are a full of Sakura in Tokyo,now. I had an experience of running in the night enjoying Sakura viewing six years ago.
http://nasser.blog.so-net.ne.jp/2007-03-30
So I invited my colleagues to run together after work to enjoy Sakura along the Meguro river. The distance from Shinagawa to Nakameguro is 5.5km.
It was so wonderful scenery like a Sakura tunnel. Runners in Tokyo should run on this road.