"Dominating Brazil's beautiful capital and affording a magnificent panorama of the city and it's harbor, Mount Corcovado has hitherto served no utilitarian purpose. But a wireless plant will soon stand on it's summit, over 2,000 feet above the city. This sketch gives an idea of the hazards of the construction and the view offered from the world's loftiest radio station."
Mount Corcovado is actually 2,310 feet high and sits in southeast Brazil overlooking Rio de Janeiro. Today it's better known for the somewhat creepy concrete statue "Cristo Redentor" of Jesus Christ that sits atop the peak today. The statue was unveiled on October 12, 1931. But this too has a peculiar connection to radio history. In the opening ceremony, the statue was lit by a battery of floodlights turned on by radio control by Guglielmo Marconi, stationed 5,700 miles away in Rome (supposedly). So what happened between 1923 and 1931?
First of all, prior to 1923 the summit wasn't exactly bare. Even in 1918 there was a rail road that went to the summit strictly for the benefit of tourists who wanted to take in the view. There was already at least one radio station SPY, whose call sign is ungoogleable today. A third easily confused set of calls "SPE" was assigned to Praia Vermelha. So let's go back further... Brazil declared its independence from Portugal in 1822. They didn't get that in writing until 1925 but let's not mince words. To celebrate 100 years of independence they planned a centennial exposition, and they wanted to launch a new radio station over Rio de Janeiro as part of the event. They awarded a contract to Westinghouse, who shipped down the necessary equipment, men and materials and hauled it up the mountain on that aforementioned cog-wheel tourist railroad. More here.
Two 125 foot masts were erected and a 153 foot, 6-wire aerial for the 750 watt station. It was assigned the call letters SPC and operated on 450 meters. The inaugeral broadcast opened with a speech by President Pessoa. A telegraph line was run so it could broadcast speeches and operas from the city below. The station was originally planned to be temporary but it was so popular that it's life was extended. It was broadcasting as late as April of 1923. RadioWorld, Wireless Age and many other radio publications marked the debut of the station. More here.
But since 1920 a religious group called "Catholic Circle of Rio" had it's eyes on that peak. The group organized an event called Semana do Monumento "Monument Week" to collect money for the building of the statue. Construction supposedly began in 1922. It makes it difficult to account for the SPC broadcasts described in April of 1923. Regardless, the station was decommissioned by that Spring at the latest.