Passengers on the No 12 bus will be able to catch an open top version throughout July and August, starting this Saturday. The route runs between Peckham Rye and Marble Arch. Standard fares will apply and buses leave Marble Arch at 10.10am, 12.45pm, and 4.10pm, and from Peckham Rye at 9am, 11.25am, and 2.55pm.