Time Out says
Three circular routes - Historical, Modern and Monumental Madrid - cover the major sights in the centre, Salamanca and the Retiro. Good places to board include Sol, Gran Vía and the Plaza de España, but the tickets (bought on board) enable you to hop on and off all day. A reasonable commentary is available in various languages, via headphones.
Felipe IV, s/n (junto al Museo del Prado)
|Price:||Tickets €15.30; €8.40 6-16s; free under-6s.|
|Opening hours:||Tours 21 Dec-20 Mar 10am-7pm daily. 21 Mar-20 June 10am-9pm daily. 21 June-20 Sept 9.30am-midnight daily. 21 Sept-20 Dec 10am-9pm daily.|