Convenient trasportation access using the Toei line to Tsukijishijo.  

Highly recommended experiece, though one should go there really early in the morning (4.30 - 5am) to experience the real Tsukiji.

One of the best things, apart from strolling around the great amount of fish "stores" is having breakfast at one of the sushi and fish restaurants around the market. The best ever sashimi one can try in Japan is there!!