Tate Modern is a real time commitment — fit it in only if it's a priority.
Allow 1.5–2.5 hrs.
A converted power station with a cavernous Turbine Hall and a free river-view terrace, plus a strong free collection (Rothko, Picasso, Warhol). Polarising — some find modern art baffling, others love it. Best paired with a South Bank walk over the Millennium Bridge.