ROSL's closest tube station is Green Park (Piccadilly, Jubilee or Victoria lines). Take exit marked Piccadilly (south side), walk past the Ritz Hotel, and turn right onto Arlington Street. At the end of Arlington Street there are some steps, go down these steps and turn right where you will find the entrance courtyard to Over-Seas House (approx. 7 minutes).
The following buses stop outside Green Park tube station on Piccadilly: numbers C2, 9, 14, 19, 22 and 38, running west to Hyde Park Corner, Victoria and Knightsbridge, and east to Piccadilly Circus and Holborn.
Travelling west on the A4 (Piccadilly), turn left onto St James's Street and second right into Park Place cul-de-sac, Over-Seas House is at the end. If there is no space in the Over-Seas car park, alternative parking may be found in the NCP Car Park on Arlington Street off Piccadilly.