Asakusa's Sensoji complex is best seen at night. This is Hōzōmon the inner of two large entrance gates, the other one being Kaminari-mon. Hōzōmon was used to house treasure and precious scrolls.
Throughout summer Sensoji is floodlight until 11 pm and visitors can move around freely. I would add though be respectful when taking photos as it's a working temple, people will be there praying especially on the steps of the main hall.
To get there take the Ginza line (gold line) to Asakusa Station (last stop) take exit 1 or 3. Make sure your camera battery is charged - Enjoy!