Have you ever wondered what it would it be like to visit the Apollo 11 landing site? We've been talking about how we'll vacation on the moon since before Apollo 11 even launched. The Hilton hotel chain first publicized its concept of a lunar hotel back in 1967: an underground resort with a glass observation dome so bar patrons could watch the Earth rise over the rocky lunar horizon.

"I firmly believe that we are going to have hotels in space, perhaps even soon enough for me to officiate at the formal opening of the first," the chain's then-president Barron Hilton told the American Astronomical Society in 1969. In the late 1990s, Hilton again dabbled with ideas for hotels in lunar orbit or in domes on the surface.

Today, a handful of companies are developing their own plans for business on the moon. Google X-Prize competitor Moon Express wants to mine elements like platinum, uranium, rare-Earth elements, and even water ice on the Moon, and that's probably a good indicator of what the first development on the Moon will look like: industry, research stations, and maybe refueling stops for spacecraft heading further out into the Solar System.

But since space tourism is already on the commercial spaceflight industry's radar, it's likely that tourism in some form may be a part of the lunar landscape in the next few decades.

There will be a lot to see on the moon, especially for history buffs. The Apollo 11 landing site, where the first humans set foot on the moon, is the most obvious choice, but as future tourism brochures will be quick to tell you, there's more to explore. Other points of interest on your hypothetical moon tour include the crash site of the Soviet Luna 2 probe, the first man-made object to land (using the term very loosely) on the moon; the fourth-stage rocket from the ill-fated Apollo 13 mission; the Soviet Lunokhod remote-controlled lunar rovers from the early 1970s; and the lunar rovers from Apollo 15, 16, and 17, complete with the tracks they left behind.

"I rank it right up there with the creation of fire or any other of the very important technological changes that happened during humanity's history," said archaeologist Beth O'Leary, founder of the Lunar Legacy Project.

But what will it actually be like to visit these sites? Will there be a museum? Will the gift shop still sell those pressed pennies?

One vision of what that might look like includes putting the lunar landing sites under glass.

Welcome to the Archaeo-Dome

A dome, probably made of the same high-temperature quartz glass that makes up the windows of the International Space Station, would cover and enclose the site, so visitors could see everything without disturbing the astronauts' footprints or the things they left behind. For the Apollo 11 landing site, the dome might enclose the lunar lander, a seismometer and a laser reflector set up about 80 feet to its south, an arc of discarded tools, waste, and other items a few yards to its west, and maybe even a trail of footprints stretching about 160 feet to its east.

Visitors would pathways of handholds across the top of the dome to look down at the landing site from above, or around its edge to view it from ground level. Signs on the outside of the dome could give visitors more information what they're seeing: "This is a scientific instrument used to measure the distance from Earth to the moon," for example, or "Neil Armstrong used this urine bag." People will want to know these things.

"My idea was to erect a kind of transparent dome over these artifact concentrations, one that would not have its own atmosphere but would serve to both shield the sites and to allow for visitors – researchers, tourists, etc. – to float over the sites using handholds arranged on top of the transparent dome," said archaeologist Peter Capelotti, who first proposed the idea, which he calls an "archaeo-dome," in a 2009 paper. "So the basic concept is to keep visitors and their footprints completely off the site, protect and shield the site, but at the same time allow visitors to view the site in plan, from above."

The dome would serve the same purpose that interpretive trails, guides, and handrails serve at important sites here on Earth – keep people's feet off the most sensitive spots while giving people a good view of the site. As we've learned at sites here on Earth, tourism can damage historical sites irreparably. The steps of the Temple of Apollo in Pompeii, protected for centuries by a thick layer of volcanic ash, are now wearing away beneath the soles of tourists' shoes. In California, vandals have painted graffiti over ancient Native American rock art.

Once that happens, there's no repairing it or getting it back. Part of our species' story is gone forever. And it would be all too easy for a bored teenager to scuff up Neil Armstrong's footprints, or for a souvenir-hunter to grab a discarded space-boot from the toss pile west of the landing site.

The enclosure would also protect the lunar historic sites from the constant bombardment of small meteorites, extreme temperature changes, and unfiltered solar radiation that, as we speak, are slowly wearing down the stuff 20th-century astronauts left on the Moon. And since it wouldn't be pressurized and filled with air, it will maintain the airless environment that's kept the Space Age artifacts so well-preserved so far.

If the whole thing sounds a little far-fetched, it's actually not that different from structures that have already been built to protect fragile, important sites here on Earth. In Cartagena, for instance, visitors can look down at ancient Roman baths, upper-class homes, and a forum from an elevated walkway and deck, made of glass and steel, which covers the site. The structure helps protect the Roman ruins from vandalism and the elements and gives visitors a glimpse into the past.

"You see related concepts at, for example, the Acropolis Museum, or the Amann-Canovas-Mauri deck over the Roman site in Cartagena, Spain, or even in the design of the new opera house in Oslo, where visitors actually walk on the roof," said Capelotti. Of course, tourist sites on the Moon may end up looking very different, if they include any buildings at all, but this is one possibility. And before it ends up on the Moon, engineers could test the idea here on Earth.

"The idea was eventually to test such a concept with a model of such a transparent dome emplaced over an archaeological site, or a mock-up of one, somewhere off the coast of Florida or, more appropriately, in a freshwater lake where conditions could be made to simulate a visit to the Moon," said Capelotti. "I also envisioned such a project being employed at any number of exploration sites in the Arctic."

Who's Running This Place?

If you visit the Apollo 11 viewing dome someday, who will be selling you your admission ticket? Capelotti envisioned this as a NASA project, but it could as easily be run by a private company, maybe under contract with NASA. NASA's budget is less than one percent of the total U.S. budget, and there are a lot of other places in the solar system that money has to cover. To get NASA to fund a dome over the Apollo 11 site, the technology would have to be more affordable than it is today, and the agency would have to see controlling tourist access to sites on the Moon as more immediately important than, say, landing in Titan's ocean, putting a submersible beneath Europa's ice, finally getting a closer look at the ice giants, or putting people on Mars.

On the other hand, a lot of commercial spaceflight is based on the idea that if you spread costs around, it's easier to afford to build things like the Falcon Heavy rocket – which is why United Launch Alliance, SpaceX, and others work with multiple governments and a private corporate customers. So if they see setting up a historical site as another way to make money and spread around the cost of setting up shop on the Moon, they might go for it.

NASA might even make setting up that kind of protection a condition of operating in certain areas of the Moon, or they might issue a contract to a company like Moon Express to do the work and maintain the structures.

The big sticking point is that, according to a 1979 treaty, no one can own land on the Moon. Countries – and eventually companies – will own whatever objects they leave there, but they won't own the lunar ground they're sitting on. So, for instance, if you wanted to cause trouble on the Moon, you could be arrested for stealing Buzz Aldrin's discarded overshoes, but not for wiping away the footprints he made with them. And that raises some tough legal questions about whether the U.S. government, a private company, or the UN could actually build a dome to limit visitors' access to the lunar sites, or whether anyone could stop a private company – or another nation – from building one if they wanted to.

In 2011, NASA issued a set of guidelines politely asking other space agencies and private companies to keep off the historic lunar sites. The guidelines recommend keeping spacecraft and rovers at least 75 meters from the Apollo 11 descent stage, for example. But they're guidelines, not laws or regulations.

It's an issue that's going to have to be resolved as things move forward, and hopefully as private spaceflight progresses, the U.S. government and others will be nudged toward sorting it out. But archaeologists and historians here on Earth say it's time to plan ahead – and while they're mostly concerned about legal protections for these incredibly valuable sites, it's not really too early to start thinking about how people might one day interact with that part of our past.

Don't Start Packing Yet

When should you start making vacation plans?

The first lunar tourists – two unnamed people who have paid SpaceX an unspecified (but probably very large) amount of money for the chance to crew its Dragon 2 capsule on a lunar flyby mission – could blast off within the next three years. SpaceX says the mission is scheduled for mid-2018, but since the Falcon Heavy rocket still isn't operational, and it's not clear exactly when it will be ready to fly, 2020 may be a more realistic estimate.

Most of the current tourism plans are focused on getting people into orbit around the Moon, rather than giving guided tours on the surface. But if lunar tourism takes off – which isn't a given at this point, partly because the price tag is astronomical – then eventually people will want to see the sites on the ground. Several commercial space companies are working on plans to put equipment and eventually people on the lunar surface for the first time since 1972, but the first several missions will probably be focused on things like mining or research.

Predicting timeframes in commercial space is a challenge. Hilton started talking about building a hotel on the Moon before Apollo 11 had even launched, after all, and a few years later NASA's lunar program had shut down entirely. More recently, SpaceX and other spaceflight companies often have to postpone commercial missions and test flights, so it's hard to really know when something will launch until it launches. With private interest in the moon gaining momentum, there's more interest in our rocky neighbor than there's been in over 40 years, but – as in the early 1970s – that could change with a shift in the economy, or if investors simply lose interest in the projects.

Realistically, it's unlikely – but not impossible – that many, if any, of us will ever climb the outside of a glass dome on the moon and look down at the remains of humanity's greatest achievement. But our grandkids might take their grandkids there on vacation someday. In the meantime, you can take your own lunar history tour with images from NASA's Lunar Reconnaissance Orbiter.