Host a world’s fair and chances are you will end up with a cultural icon. It happened to Paris with the entrance arch to its Exposition Universelle of 1889 — now better known as the Eiffel Tower.

Similarly, New York’s World’s Fair of 1964–65 left Queens with its defining symbol, the Unisphere, etched into even broader consciousness after its starring role in the science-fiction comedy “Men in Black” (1997).

The Queens Museum of Art, with the Unisphere on its doorstep, has a pair of exhibitions that delve into another legacy of the fair, the nearby New York State Pavilion. This was a visionary structure designed by Philip Johnson and dubbed the “Tent of Tomorrow.” Although in disrepair, its futuristic design, dominated by three observation towers with highly distinctive circular decks, vies with the Unisphere as the defining feature on the park skyline. Seen from automobiles traveling between the city and both its airports, it is, inadvertently, a surrogate Statue of Liberty for the airborne immigrant.

The shows celebrate the moves afoot to restore the pavilion and, in particular, what was its principal attraction, the terrazzo floor replicating the Texaco Road Map of New York state. This was the world’s largest map.

“Back to the Map” is an architectural and historical display that explores many aspects of the map, its construction, its reception, and its physical decline. It also details the procedure for painstakingly restoring this monument, a task undertaken by the University of Pennsylvania conservation team in collaboration with the New York City Department of Parks & Recreation. Visitors can watch conservators at work in a sectioned-off corner of the gallery behind protective screens.

“Empire State Pavilion,” meanwhile, a show within the show, is a photographic installation by the British artist and architectural theorist Anthony Auerbach. This documents with bizarre exactitude the state of desuetude of the terrazzo floor the week before restoration work began, in October 2006, with the removal of years of stray detritus and weeds.

The shows, with their obsessive but contrasting senses of time and place, seem distinctly appropriate not just to the state pavilion renovation, with all its “back to the future” connotations of time past and time regained, but also to the Queens Museum, an institution steeped like no other in its World’s Fair heritage. The World’s Fair attracted 6 million visitors. It was the last such fair after more than a century of such costly, gaudy extravaganzas, which were both imperialistic and humanistic in their intention and scope. The QMA, which was founded in 1972, on the eve of an inauspicious period for New York’s economic fortunes, always feels like a fading attraction in a kind of cultural ghost town.

Indeed, it is a tenant of this past, occupying the New York City Pavilion of both the 1938 and 1964–65 World’s Fairs. That in itself is not unique — Paris’s Petit Palais was also a fair building (from 1900). With desultory holdings of its own, however — some Tiffany glass, for instance — the QMA’s singular glory, taking up a sizeable chunk of its ground space, is also a relic from 1964. This is the Panorama, a sprawling 9,335-square-foot model of New York, updated in 1992 and 2006.

The Texaco Map is now being celebrated as a landmark in the history of Pop art, as the first instance of this modern art movement literally going to the masses with its appropriations from mass culture. The show argues that, in his Empire State Pavilion, Johnson himself underwent a transformation; it represented a staging post in his development from a Miesian, purist, highbrow Modernist to the first Postmodernist, with his jokey, referential AT&T Building (now the Sony Building) in 1984 with its notorious Chippendale summit. The sci-fi quality of the state pavilion has a humorous, populist appeal in its fluid, organic twirls. Furthermore, Johnson commissioned major outdoor murals from contemporary artists who included founding fathers of American Pop.

Some vintage black-and-white photographs document works by the 10 artists, including Robert Rauschenberg, Andy Warhol, and John Chamberlain, that hung outdoors around the circular Theaterama. But it was the map itself that was the major Pop appropriation, realized in terrazzo, the intricately textured faux-marble material. Like all the building work and features of the World’s Fair, it was intended for a short life and built to budget accordingly. After the fair, the state pavilion served as a rock venue, and then the floor was covered as an ice skating rink. Naturally, this left a severely cracked, fissured surface, a shadow of its former glory.

It seems somewhat surreal to expend fastidious restoration efforts on a Pop decoration barely half a century old as if it were a Ravenna mosaic. It almost showcases the shallow history of Queens and its architectural attractions to take such care, rather than just remake the floor from scratch.

Mr. Auerbach was similarly nutty in his scientifically exact documentation of the material state of the map’s decay as of October 2006, but more knowingly so. Originally an expressionist-realist draftsman, in the style of Lucian Freud and of his famous though unrelated namesake Frank Auerbach, Mr. Auerbach latterly ventured into Monty Python-like neo-conceptual projects inspired by the subversiveness of the 1960s avant-garde Fluxus movement, often working with collaborators under the mock-conspiratorial guise of the International Necronautical Society.

His “Empire State Pavilion” project surveyed the map using an aerial reconnaissance technique in which the camera was suspended 7 feet up on a moving scaffold to capture a field of 6 feet by 4 feet. The resulting film is presented in the installation in two ways: A digital slide projection presents the state, county by county, on a floor-bound horizontal pedestal. And selected transparencies can be studied on low, small tables through stereoscopic lenses (a viewing arrangement familiar to New York gallery-goers from William Kentridge’s recent exhibition at Marian Goodman Gallery) to give a three-dimensional sense of the surface and life just above it.

This project is primarily conceptual, in that what is to be savored is not so much the presentation itself as the intentions and implications of the fact that it was undertaken. Philosophically, it adds a welcomely eccentric slant to the QMA’s determination to re-create its past, a fleeting, essentially kitsch moment of glory, by mimicking conservational precision in the service not of re-creation but decay.

Mr. Auerbach’s enterprise recalls the Borgesian fable (itself beloved by the late French philosopher of simulation, Jean Baudrillard) of an empire that creates a map so detailed it ends up the same size of as the empire itself. It prompts the thought of what might have resulted, had Mr. Auerbach juxtaposed his aerial shots with corresponding Google Earth satellite images of the actual terrain.

Until May 4 (New York City Building, Flushing Meadows Corona Park, 718-592-9700).