At least, not if you're an ordinary couple from the Gold Coast visiting the capital on a cloudy weekday morning.

But Duncan and Neryl McLay had the distinction on Wednesday of being declared the 50,000 visitors to the library's Mapping Our World exhibition.

Having booked to see the major summer show months ago as they planned their trip to Canberra, and showing up at the time allotted on their timed ticket, they were more than a little surprised to be nabbed at the entrance by director-general Anne-Marie Schwirtlich.

She presented them with an exhibition catalogue and announced they would be personally escorted through the show by one of the show's curators, Susannah Helman.

Ms Schwirtlich said the library had decided to mark the occasion because the show, an exhibition featuring many of the world's greatest maps, was exactly halfway through its run, and had already exceed expectations in terms of visitor numbers.

Having already seen 50,000 people coming through the doors, especially throughout the quiet summer period, had been a boon, as the goal was to welcome 100,000 visitors before the show ends in March.

But in the first week alone, more than 6500 people saw the show, compared to 2500 in the opening week of the library's last blockbuster, Handwritten.

Ms Schwirtlich said she had always known the exhibition, which has free entry but with a timed ticketing system, would be popular.

"I think there's an endless quest we all have to place ourselves," she said.

"Where do I fit in, where do I live, where does that fit in? And how can I find my way or my bearings from the neighbourhood all the way through to round the world? I think that explains its popularity."

And it was no surprise that the day's star visitors were from out-of-town; exhibition-goers, many of them avowed map-lovers, had been coming from all over the country.

She said she had come across a man from Emerald, in Queensland, who had asked for just one Christmas gift – a trip to the capital to see the maps.

While here, he also discovered the extent of the library's vast mapping collection, and has vowed to return.

And as for Mr and Mrs McLay, the morning was off to an unusual start.

Mr McLay said he had been keen to visit the maps show to see how Australia had developed over the years from a distant unknown to a strange continent slowly taking shape over centuries of map-making.

The couple had family in Canberra and visited every couple of years around Christmas, and had a packed schedule this week.

"It's good that the galleries put something on around this time of year. There are usually things on," he said.

"We've got a long list of other things to so but haven't got all that much time so we have to prioritise."

Mrs McLay said she had already taken in the Elvis Presley exhibition at the National Portrait Gallery, and had booked tickets to see Gold and the Incas at the National Gallery of Australia later in the day.

Mapping Our World: Terra Incognita to Australia, runs at the National Library of Australia until March 10.