Aerospace and Electronic Systems Magazine March 2017 - 26

Coltano: The Forgotten Story of Marconi's Early Powerful Intercontinental Station

WWII AND THE END OF COLTANO STATION
Only scarce information is available on the calamitous events that
happened in Coltano during WWII. The most reliable source is a
brief report containing the memories of Narciso Baroni, a technician of the station who was an eyewitness of the events, later transcribed by his daughter Matilde [36]. According to Baroni's narration, when the war broke out all the station's staff was militarized
and the whole facility was under armed surveillance. A team of
military technicians went to Coltano, trying to restore the old VLF
equipment and use them for communications with submarines. The
attempt was unsuccessful, however. Next the station went under
complete control of German forces and the civil radio service was
interrupted. The station was never used by the Germans, but remained partially operative for military and government communications. Oddly enough, the Coltano center was spared during the
heavy Allied bombings that severely hit Pisa more than 50 times,
during 1943-1944. In summer 1944, under the pressure of the
advancing Allied army, Germans withdraw from Pisa and moved
north. Prior to leaving Coltano, however, they blew up the building
of the new radio and all the antenna towers of the radio center.9 The
building of the old Marconi station, which had not been operated
for a long time, was spared. On July 20, 1944, the Germans mined
and blew up the Solferino bridge over the Arno river, in downtown
Pisa. The telegraphic cable that passed under the bridge, joining
Coltano with Nodica, was cut off. This was the final act marking the
death of the Coltano center. Curiously enough, that day coincided
with the death of Guglielmo Marconi (in 1937), and the birthday of
his daughter Elettra (in 1930).
In those difficult war days, metal wreckage was a valuable
good and therefore the site was sacked: the fallen antennas were
dismantled and the metal sold on the black market, together with
wires, cables, and equipment parts. Even the metal wiring of the
antenna grounding systems was dug up and sold. Nothing was left.

Figure 17.

The original 2 kW SW transmitter mod. SWB4 "Pechino" by Marconi
Wireless Co., London, that sent the signal from Coltano to Rio de
Janeiro in 1931. Now displayed at the Historic Museum of Communication, at the Ministry for the Economic Development, in Rome, Italy.

with the Italian concession in Tianjin, China, 8250 km away. In the
same year, the first public service from land to vessels was activated. The first served ship was the Italian liner Conte Rosso, which
kept regular contact with Coltano while sailing to Shangai, 9200
km away. The service was soon extended to the Rex and the Conte
di Savoia liners, sailing to New York, 6650 km away, and to the
Duilio and the Giulio Cesare liners, sailing to Cape Town, South
Africa, 8670 km away [11], [34]. The map in Figure 18 shows the
areas served worldwide by the SW transmitters. In 1935, two new
shortwave transmitters, supplied by Marconi Wireless Co., were
installed: a 56 kW transmitter for radiotelegraphic services and a
35 kW transmitter for radiotelephonic services [35].
The Coltano radio center was regularly used for SW service
until the early 1940s. WWII was already raging however and the
Coltano saga was approaching its dramatic end.
26

POSTWAR
The disgraceful destruction and the subsequent postwar events
doomed the Coltano radio center to an undeserved oblivion. Actually, the maritime radio service was transferred to the Prato Smeraldo site, near Rome, and the abovementioned Narciso Baroni was
appointed as its first director. Coltano's antennas and station, instead, were never rebuilt and the site was finally abandoned. After
more than three decades of distinguished service, the Coltano radio center ceased to exist. In 1946, the monarchic regime ended in
Italy and the Republic was established. The former royal estate of
Coltano, which included the survived Palazzina Marconi, became
a state-owned land, located within the municipal area of Pisa.
However, an adjacent area was chosen again to host some important telecommunication infrastructures. After all, the site had
been personally selected by Marconi and this was sufficient motivation!
9

Sources from the Italian resistance movement refer that the antennas were destroyed on June 14, 1944, but do not report the
date of destruction of the main station building.

IEEE A&E SYSTEMS MAGAZINE

MARCH 2017

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