A visit to the Toyosu Fish Market is a highlight of many Tokyo trips and the tuna auction remains the biggest draw. Watch for free from a gallery above the action (arrive early to secure your spot) or an observation deck on the auction floor. For the latter, you need to apply for access and spaces are limited, assigned by lottery system. The entire registration process is in Japanese, so hiring a local guide or attending as part of an organized auction tour is the ideal way to overcome the language barrier.
Alternatively, visit independently or as part of a small-group or private Tokyo city or food tour to explore the Toyosu Fish Market stalls and restaurants with a local. Some tours combine Toyosu and Tsujiki into one convenient half- or full-day excursion and some also include a sushi-making workshop.