The Prime Minister Peter O'Neill has never been there in his term of Parliament.
After the trip, Mr Polye said, he learnt that PNG faced trade deficit there.
Following briefings from customs and defence officers, he added that this trip would help the next government, which he is confident of leading, to draft policies and legislations to address border issues.
He stated that he got relevant information needed to improve trade and other issues facing both countries.
Polye was on a three-day roadshow for his Triumph Heritage Empowerment (THE) party's candidates for Sandaun province.
"Trade worth more than K3 million takes place at the border without any proper control by authorities. It adds to the tally of total capital outflow," he said.
The Opposition Leader said both governments needed to encourage businesses to build permanent buildings on each side of the border to sell their items.
The makeshift buildings, he said, must be demolished to make way for the permanent ones.
Photographs courtesy of PNG Opposition Media Unit.