National Museum of Scotland: World of wonder comes to life in the capital again

• A reflection of the new interior in the Millenium clock

IT IS A MOMENT thousands from the capital and beyond have been waiting more than three years to see. The Royal Museum building, a light-filled Victorian edifice whose soaring Grand Gallery was for generations a cherished city gathering place, reopens tomorrow as the beating heart of the National Museum of Scotland (NMS) after a 47 million transformation.

The NMS director Gordon Rintoul says that the building that had for years been "a little bit sad and a little bit tired", is now "an entirely new museum".

"We are entirely confident that those who knew the building almost won't recognise it. Those visiting Edinburgh for the first time will be really quite surprised. In most capital cities of the world you might have to visit four or five museums to get what you have here in one place. Essentially it's the whole world under one roof."

• Video: Behind the scenes at the revamped National Museum of Scotland

The public and the critics will be talking about it for months. A flood of locals are certain to converge on the building this summer. It opens at 10am tomorrow with 36 galleries, including 16 entirely new ones.

The NMS on Chambers Street, say staff, is poised to reassert its place as the leading public museum in the country uniting 8,000 objects on show thanks to the Scottish scientists, collectors, and adventurers who brought them home.

The changes will confront visitors from the moment they arrive. Rather than clambering up the Royal Museum's steps and pushing through vintage wooden doors, they now enter at street level, into a vaulted, roomy space with restaurant and shop, previously a storage basement.

An escalator leads up to the Grand Gallery, where the museum's showpiece, cleared of clutter (as well as the much-loved goldfish ponds) focuses attention on objects from a boat-size Maori feastbowl retrieved from a cellar, to a Victorian roofed fountain. The balconies now boast a new caf and a stunning sculpture walk.

• Analysis: At last there's light at the museum of everything

Highlights include the UK's largest single museum installation, the Window of the World, where 800 objects are shown in a display running through three floors of the gallery, 18 metres high. They range from the world's largest piece of scrimshaw – two giant sperm whale jawbones, with engravings of whales and whaling by 19th-century seamen – to stunning seashells, Buddhas, teapots, and a girder of the Tay Railway Bridge, which disastrously collapsed in 1879.

"We just assembled objects because they were surprising or beautiful or thought-provoking," says Alex Hayward, the museum's keeper of science and technology. The Window on the World includes 19th-century mechanical models, created at the museum, that operate on the touch of a child's hand. He calls it a "cabinet of curiosities" for Scotland.

The theme of the museum's new approach comes is on show in the Discoveries gallery, just off the Grand Gallery, with highlight objects linking Scots to the exhibits as collectors, explorers or inventors. It ranges from the Assyrian relief donated by Sir James Young Simpson, the discoverer of chloroform, to a silver and coconut shell goblet with which James Bruce, the first European to survey the Blue Nile, toasted the health of George III in 1770. It's also the new home of the popular Millenium Clock.

"Really running through all these galleries is the Scottish thread," says Rintoul. "It really emanates from that great tradition of adventurers, or entrepreneurs, or Scots in the world as colonial administrators or missionaries or engineers, and bringing things back, sending things back to Scotland. In many ways you've got the story of Scots engagement with the rest of the world."

The Natural World galleries seem set to deliver an unforgettable moment of wonder for a new generation of Scottish children. The museum's stuffed animals and skeletons were once displayed in dark cabinets.

Menacing dinosaurs now tower over visitors while whales and sharks, a hippo and an albatross are suspended through three floors in the "Wildlife Panorama" with film screens that bring them brilliantly alive.

Adult visitors may feel more at home in the World Cultures galleries – themed displays over three floors that include Facing the Sea, the only UK gallery dedicated to the cultures of the South Pacific. With galleries like Patterns of Life and Inspired by Nature – the latter looking at how artists across countries and times draw on nature for their work – they attempt to link a vast array of objects. Highlights include a 11.3 metre Native Canadian memorial pole and Tibetan Prayer Wheel House made for the museum in 2009.

Staff have already begun meetings on the 11 million next phase of the revamp, in a new round of fundraising, to pay for new galleries in the next three or four years and expand the Chambers Street frontage with a new pedestrian space.

For architect Gareth Hoskins the museum represents eight years of work, since he was chosen as the head of a relatively new Scottish firm to take on the redevelopment masterplan. Hoskins worked with the US museum designer Ralph Applebaum, in the same team that delivered the Culloden Battlefield Visitor Centre. Applebaum calls the project a return to the vision of the "universal museum" with "great stories well told".

Hoskins, now a veteran of several major museum projects, says his design reflects the idea of a building and the collections working together, rather than "fighting each other". He contrasts it to Glasgow's Riverside Museum, where the transport collection is housed in an uncompromising new showcase building by the Zahar Hadid. The NMS, unlike other major museum projects in Scotland, had made the "very brave" decision to pick the only Scottish team, he says. Asked if it had paid off, Hoskins says with a smile: "I will let everybody else be the judge of that."