OTTAWA - Prime Minister Stephen Harper has a vision for Canada centered not on its highly populated southern cities but instead in its vast and empty North.

Over five days, from Whitehorse, Yukon, to Cambridge Bay, Nunavut, and Churchill, Man., and in sweeping and patriotic terms, Harper laid out his intention to make the northern territories an economic powerhouse for the nation.

"Even Canadians who have never seen its wild and vast beauty know in their hearts that the North is Canada's call to greatness and that our country's biggest dreams lie in our highest latitudes," Harper said during the tour.

The common thread running through this annual northern trek - Harper's seventh - was tapping into the potential wealth and the resources below the permafrost.

He called the mining boom in the Yukon - that some economists predict will drive the territory's economy for at least a decade - part of Canada's "national dream."

In the Northwest Territories, he spoke of how the warming Arctic could open up potentially lucrative shipping in the Northwest Passage.

And on navy warship HMCS St. John's, following a display of the capabilities of Canada's elite special operations forces in a simulated national security exercise, Harper spoke of Canada's readiness to defend the "true North strong and free" and its resources.

But the plans face numerous challenges -- and have critics from a variety of corners.

The cost of living north of 60 can be stratospheric. A pack of 24 water bottles in Cambridge Bay costs $50; buying the basics in Norman Wells, N.W.T., - eggs, milk, bread and coffee - can range between $50 and $100.

Remote communities like Cambridge Bay face many social problems.

The isolated hamlet on the shore of the Beaufort Sea may be getting a new High Arctic research station and, lately, visits from cruise ships passing by, but it still has upwards of 40% unemployment. Four families can be found crammed into one house.

Northerners across Canada who spoke with media travelling with the prime minister sometimes expressed fears development would destroy the rugged natural beauty and the remote way of life that kept them there despite the challenges.

Infrastructure problems and labour shortages hamper business development. Environmentalists are raising the alarm over climate change and melting sea ice.

Alongside those issues, next year Canada faces its deadline to submit its continental shelf boundaries to the UN and takes over as chair of the Arctic Council, an intergovernmental body of eight Arctic nations.