Trying to plan a perfect three days in London? Although three days is never enough time, here's what we suggest. Spend two days in the city’s heart; peruse Picassos and borrowed treasures at London’s best museums. Row through a royal park. Dig through kitchy Portobello Market. Spend a day taking in iconic London sights from Southbank before heading to East London for a taste of urban hip. End your three days with a sky-high cocktail and fabulous view over London.