Sensoji temple is probably most famous temple in Tokyo, which all tourists, domestic or international, would visit during their stay in Tokyo.
Located in Asakusa district, which was the biggest entertainment district in Tokyo till mid 20th century, Sensoji temple built in 645 is definitely the main tourist attraction of Asakusa. It is the oldest remaining temple in Tokyo.
Then, Kaminarimon gate is the face of the temple. Kaminarimon means Thunder gate in Japanese and beyond the gate is the famous Nakamise-dori shopping street which leads the temple's buidling.
Sensoji is one of the busiest worship places during New Year's day. The number of worshipper is after Meiji jingu shrine, which means Sensoji is the most popular temple in Tokyo.