Witthayu Road (ถนนวิทยุ), or Wireless Road in English, was built in 1920 to connect Rama IV Road with Phetchaburi and Ploenchit roads. At the southern end is Lumpini Park, the first public park in Thailand built during the reign of King Rama VI. In those days, the opposite side of Lumpini Park, on the corner of Witthayu and Rama IV Roads, used to be the location of the first radio station in Thailand. Therefore, this road was given the name “Wireless Road”. The area of the station, on the corner of Witthayu and Rama IV roads, later became the site of the Armed Forces Academies Preparatory School (1961–2000), then the Suan Lum Night Bazaar (2001–2010). The area is now being developed as a mixed-use megaproject called One Bangkok.