The splendid rounded-glass home of the mayor and the London Assembly is a Norman Foster design.
Weekday visitors can explore the exhibition space and walk to the second floor, which offers a view of the Assembly Chamber.
Parts of City Hall are open Monday-Thursday 8:30 am-6 pm and Friday 8:30 am-5:30 pm. Free.
The Queen's Walk (Tube station: London Bridge or Tower Hill), London SE1.