Map: Darwin 0800 Before text messages, e-mail and Twitter, there was the telegram, and this week people in Darwin will be able to send a telegram to anywhere in Australia for free.

Back to Morse Week commemorates the construction of the Overland Telegraph Line in the 1870s which connected Australia to the rest of the world.
Until next Friday, messages will be transmitted through morse code from Lyons Cottage in Darwin to Rundle Mall in Adelaide.

Telegraphist Barrie Barnes says a telegram will then be transcribed and posted.

"Australians 50, 60, 70 years ago communicated with each other via telegram, which was transmitted between post offices by morse code," he said.

"It doesn't run down a physical line as it did then, which was a piece of galvanised iron wire.

"It's now sent over the normal telecommunication links, but it does traverse the same route as the overland telegraph line."

It is the 20th time the event has been held in Darwin.