Original: Ruislip, opened March 1, 1910 by the District; first served by the Piccadilly line October 23, 1933 (some trains terminate here in Monday-Friday peak hours).
Simplified: Rayners Lane, opened March 1, 1910 by the District; first served by the Piccadilly Line October 23, 1933 (from here to Uxbridge trains share track with Metropolitan Line, and some trains terminate here).