When you see yourself riding a landau in a dream, then such dream promises joy and satisfaction you will receive from the certain person in your life. If the landau turned over, then such dream indicates the finish of the pleasure in your life.
Dream dictionary: Landau dream meanings
…Dreaming that you ride in a landau, with your friend or sweetheart, denotes that incidents of a light, but pleasant character will pass in rapid succession through your life. If the vehicle is overturned, then pleasure will abruptly turn into woe. See Fields and Earth….