The State entity and partners PNG Power Ltd and HG Transmission PNG Ltd connected the cable at Nintul in Sinasina-Yongomugl district, Chimbu.
It marks the connection of the main trunk cabling in less than 12 months.
PNG DataCo general manager commercial Une O’Ome said it was a historic event in communication in Papua New Guinea.
He said HG Transmission would in the next two months connect customers in the main centres to cable terminate points where Internet Services Providers will provide communication services for schools and institutions along the main cable-run vicinity.
“The project has seen the completion of a stretch of 530km of cabling,” O’Ome said.
“In this final stage, we are connecting Ialibu, Mendi, Wabag, Mt Hagen, Jiwaka, Chimbu, Goroka to Yonki that runs to Madang and Lae.”
O’Ome said customers would now experience high speed transmission of data, fast broadband internet connections, communication and information transmissions.
“This is a good project and DataCo thanks PNG Power and HG Transmissions for the partnership.”
Project construction manager Ashok Kumar from HG Transmission said the company was awarded the contract in September 2014.