Disclaimer: I do not own Star Wars or Harry Potter. George Lucas (…or Disney now) and JKR do. I just write for the lolz.

The unforgiving claxon of an alarm ripped the exhausted young man from his slumber hard enough to force an involuntarily flinch and gasp all at once. Eyelids that felt lead shot open immediately, revealing two brilliant green orbs. With practiced ease, Their owner slammed his palm over the big red spring-actuated button, robbing the blaring horn of its power, silencing it.

Harry Potter sighed, rubbing both hands over his eyes to remove the grit that a few precious hours of sleep had managed to accumulate. The rusty old cot creaked loudly as he swung his legs over the side.

He'd have to hit it with a repair charm soon, lest the bloody thing fall apart with him on it.

Speaking of repairing things. The sparsely dressed wizard rose and strode over towards the user console, the only other object in the Spartan quarters he allowed himself. In recent years, luxuries such as reading, watching the teli, or even sitting down for a quiet meal were becoming harder to indulge in.

He couldn't afford those distractions anymore, so why clutter his room with them? The reason was this dilapidated place. The walls were concrete and dull gray, with obvious imperfections from the hastily thrown together forms clearly evident.

Things like air pockets that vibrations hadn't reached, aggregate that hadn't been properly mixed, and the rough joints where the material had pushed the molds unevenly, creating jogs in the otherwise monotonous walls.

Most of those, however, were just cosmetic. It was the large cracks from the growing geological stresses on the facility that worried Harry, and the moisture seeping into those cracks, slowly but surely eroding the reinforcing steel hidden within.

As dire as that sounded, the structural integrity of this place wasn't even close to being on the top of his to-do list right now.

Several sections of the screen flashed red over a plan view of the facility, while even more glowed a dull orange. The red obviously needed immediate attention. The source of his rude awakening.

"Bugger me", the raven-haired man muttered, glossing over status reports and error messages compiled by the base's computer system. He rubbed a calloused hand over his stubble. A rare but most welcome shave some three days prior. Usually, the wizard sported a beard that could rival that of his long-departed headmaster.

In a flurry of movements, his fingers danced over the glass interface, gathering more information on the malfunction messages. He paused at one point, and the frown he'd woken up with deepened even more.

"The hell? I just fixed this section yesterday!" he protested to no one in particular. Another few minutes passed while he compiled a workload for the day, which was transferred to a rectangular datapad.

With a better idea of what his workday looked like, the former British Wizard got dressed. Black standard issue combat boots, cargo pants, a plain white tee. A far cry from the clothes he'd come to favor back when he'd been enrolled in the Auror Corps.

Those garments had all but fallen apart a long time ago, charms or no. What he wore now had been found in a dusty old Pelican case, courtesy of the US military, who'd banded together with the United Kingdom to build this place. Finishing the look was a specially made gauntlet he latched onto his arm. Inside the small space rested three very special items.

A single stone, cloak, and wooden stick.

The Hallows.

They'd allowed him to watch over this place for as long as he had. Granted him a body that could not die, though he was beginning to wonder if the mind was another matter. The regular self-obviations he performed regarding the more mundane things helped. Harry estimated he'd read and re-read the contents of the Hogwarts library a dozen times over just in volume alone.

Of course useful content like that he didn't just wipe. But Novels, works of fiction were another story. Fortunately, the muggles had lots of those to occupy himself with. But as mentioned before in recent years that downtime happened less and less as the man-made structure began to waste away under time's relentless assault.

He donned a thick winter coat that had patches overtop of patches, with little of the original material left visible, and applied heating charms to himself. His quarters were near the top of the underground base. Originally they had been lower, but the time it took to ascend the thousand or more feet of staircases (elevators drew power after all) he could have already been to the surface and fixing whatever needed fixing.

The surface, right. Not a very nice place. Harry, of course, didn't know the full story of the hows and whys, and probably never would. Bottom line was that Earth was gripped in an ice age, the likes of which humanity had never experienced.

Before the last of the nuclear-powered muggle satellites went dark, they'd established that all of Earth, right down to the equator was covered in thick ice sheets.

Unbelievably thick ice.

The muggles thought it was because of pollution that blocked much of the sun's rays. Others theorized that the rapid climate change caused the jet stream to migrate further south. Reflective ice claimed the northern regions of Europe and much of Asia. More light reflected meant less heat absorbed.

Whatever the reason, they had enough foresight to prepare. The ice grew outward, creeping down the lower latitudes like an unstoppable bulldozer.

Harry had been assigned to the British Prime minister early on in his career, chosen in part because of his familiarity with the Muggles, and as such was more aware of the planet's inevitable demise than most magicals.

The few wizards that listened to his warnings were more than welcomed, considered invaluable for their abilities. But for the most part, the closed-mindedness of his magical brethren proved to be their downfall.

Iceland was still close enough to the UK to appartate.

Last time he'd been there, the deep vaults of Gringotts were all that was left. Mile thick ice slabs had physically abraded the Islands of the United Kingdom down below sea level, had the sea actually been liquid at that point. Only the lowest caverns remained, packed to the ceiling with humans, goblins and various other species.

Living conditions were deplorable. Harry had rescued as many as he could.

The base, like the bank, was of course deep underground. Far enough that the abrasive glaciers that soon dotted the landscape could not reach. Their slow passage could be heard through the solid rock, a steady grinding sound that never ceased.

To him, it felt as though they were grinding away at his psyche, and even the most honed of Occumency shields could not keep his sanity intact.

After a while, it simply became background noise. Powered by geothermal energy, in theory, this place could have functioned forever. Everything was recycled. Water, air, waste. Greenhouses grew food, bunkers full of seeds would provide the building blocks of a future after the ice.

But the size of the structure meant that only a limited amount of people could dwell here. Enough to keep a viable gene pool and carry on watching over and maintaining the staggeringly huge number of souls sleeping in the adjacent cryo storage facility. Ten thousand people. It had been planned well and did work for many years.

Right until the quakes.

The facility had been carved from the relatively new igneous rock formed by Iceland's lava flows. An area rich in thermal springs due to the close proximity of the hot mantle under their feet. Power was drawn from this hot core by pumping water down and harnessing the steam that shot back up.

Turbines. Harry had learned a lot about how muggles generated electricity in those first few years. But the lines were severed. Some of the scientists speculated that with the huge weight of the ice on the tectonic plates were shifting in ways they couldn't even begin to model. No steam meant to power.

They'd tried to majik the turbines to spin without the power of the core, but without lay lines to power and sustain the spells it was impossible. Harry and the other Wizards and Witches felt the magic of the planet fluctuate wildly as the lines themselves shifted. Hogwarts, or what was left of it was undoubtedly not even over an intersecting pair of the powerful lines anymore.

The shaking was intense and oftentimes prolonged, events occurring multiple times every day for months. Were it not for the strengthening runes carved on the concrete walls the base would have been surely destroyed. Several other countries had similar facilities as well. The surface communication lines were severed during the prolonged event. They likely suffered the same fate as the US/UK joint venture.

'Perhaps the Russians made it?' he mused, wondering for the millionth time if there was a vibrant community of Russians living underground somewhere in Asia. They opted to use massive nuclear reactors, stockpiling tones of enriched uranium and plutonium that had a half-life of tens of thousands of years. But there had no way of knowing for sure, or of contacting them.

Seismic Morse code was one option they'd tried, at least with the French Base nearby. But after days of repeating the message the decision was made to conserve power. One by one the maintenance populace went to sleep, perhaps for the last time. Eventually, only Harry remained.

With only the sound of his rubber soles hitting the icy cold rungs of the ladder, he set out.

'How long had it been now? Decades? Centuries?' He'd promised himself to keep track. But that was back when calendars meant something. And even atomic-powered clocks only lasted so long. An ever-moving mechanical clock with gears and cogs then. Yes, That could work.

Too bad he hadn't thought of it sooner. But then again who could blame him? After all, something as trivial as telling time wasn't exactly a high priority when trying to save the human race, magical and muggle alike.

All available power went to the chambers, meaning only essential systems were active. Heck, for most of the day he didn't even have life support. Not a big deal when one human had several hundred thousand cubic feet of breathable air. The scrubbers more than made up for his usage in the few hours they operated. And heat? Well, being several kilometers inside the crust the temperature was actually rather nice. A design concept no doubt. The base was a constant twenty-three degrees centigrade. Room temperature.

Harry, not for the first time considered waking one of his colleagues from long term cryo storage, both for the help and the chance to finally converse with someone after unknown years of social isolation.

It was maddening.

Despite not knowing exactly how long he'd alone, the number of years must have been quite substantial. He squashed the thought. Power in the ancient facility was already critically low. A sudden spike in consumption might be enough to cripple the entire grid. No, he couldn't risk it.

Harry opened the heavy latch at the top of the ladder that led to the emergency air shaft. He shook his head, once again done weighing the pros and cons of human company. The main entrance had long ago been sheared away by the advancing ice slabs.

Technically the air shaft had as well. Early on the remaining magicals had sealed the top with a granite block cork and tunneled sideways towards the nearest mountain peak. Constantly vanishing the solid rock had taken weeks, but as suspected, the peaks were bare, untouched by the mass of ice slowing passing below.

With a connection to the surface, the ever-present sun could once more be tapped for power. Thick glass plates shielded the solar panels from the elements, allowing their reflective blue surfaces to track the sun's progress through the sky.

Winter was always the hardest because at its peak the sun would only come up for a few precious hours. It was barely enough to charge the huge banks of deep cycle batteries originally meant as backups. Now they were tapped annually to last the long and cold nights during the winter months.

And each year they would lose a bit off efficiency. As did the panels. How much longer could he hold the place together?' Harry thought, having finally reached the horizontal stretch of the tunnel.

The way forward was pitch black. Harry had given up trying to make time to install lights along the path. Normally he'd apparate, but the problem today was not with the panels themselves but the conduits.

He slipped a focusing lens over his wand tip and muttered a lumos. The magical beam of light cut through the darkness like a muggle torch. A splendid invention of a Yank engineer he'd befriended many years ago.

Though proficient with wordless casting, Harry rarely spoke anymore so any chance to use those dusty vocal cords was gladly taken, even if it made him sound like a first year. Thick power supply lines snaked their way along the dull black floor, running from the solar cells miles above ground to 'Phoenix' base, as his friends and colleagues had dubbed it.

A silly name if you asked him, but his people hoped that one day their legacy could rise from the proverbial ashes and reclaim the planet. His people… When had he started referring to them as such? Well, he did watch over them. Labored every day to keep them alive. They were his to protect.

Soon he came across the first problem. A partial cave in over a weak section of the tunnel had damaged some of the 'smaller' armored conduits. He vanished the rubble and braced the ceiling with transfigured steel beams. Wood was easier to create, but even down here the fibrous material only lasted a few years before disintegrating.

The conduit had a sizable dent, which no doubt severed some of the copper lines hidden within. Impressive considering it was the diameter of his torso and clad in two inches of pure titanium. A quick reparo took care of the damage, the casing popping back out with a metallic screech.

Harry repeated the process further down the very long tunnel before finally apparating to the solar dome. There, he pulled one of the panels apart for routine maintenance. He'd need all of them operational for the coming winter solstice.

Halfway through the task, he paused and sat back. Though he didn't come up here very often, this was one of his favorite places. The views during the day were stunning, despite all the white. But at night, the Northern Lights put on a light show that, at least for a little while, made this gargantuan task all worth it. The shimmering greens and purples cast a faint glow over the crystalized landscape.

It was beautiful.

Harry pulled a small radio from his coat and flicked it on. For a few minutes, the silence was broken by a voice long dead, the only existing copy most likely being his dilapidated cassette collection.

A single tear slipped down his cheek, slowed by the thickening stubble. He pulled a familiar photo from his back pocket. It was a bit dog-eared but otherwise in good condition, courtesy of the preservation charms placed on it.

It showed him and his best friends, dressed in formal Hogwarts ceremonial robes. Their graduation ceremony. Because of the Horcrux hunt he, Ron and Hermione had all officially finished school with the sixth years. Ginny, Luna. Even Neville, though he did take his NEWTS in ninety-eight.

He missed them.

Harry tucked the moving picture away and rose with a grunt. There was a lot that needed to be done today. No rest for the wicked it seemed.

The panel was put together quickly and diagnostics showed it to be fully operational, though with no light to catch it remained on standby, just like the dozens of others. Harry was about to head back inside his warm lair when a faint vibration caused him to pause.

A tremor? There hasn't been any tectonic activity for a long time.

Unbeknownst to him, the steady attrition of the ice against the brittle volcanic rock had gouged a path past the peak that held the solar array. With its base compromised, the countless tons of rock were moments from falling victim to gravity, another constant that never changed.

The ground gave way. But not just where he stood. The whole peak was going. A brief sense of vertigo enveloped him as the entire dome plunged down the steep embankment and into the glacier-filled valley below.

Harry didn't even have time to think about apparating before his body re-connected with the bare rock he had, up until a moment ago, been standing on. The impact practically broke every bone in his body, along with every solar panel, the glass dome, and virtually anything else that had been on the peak. The glass semi-sphere shattered spectacularly, and the last thing Harry felt was a brief rush of bitterly cold air before being claimed by sweet oblivion.

A/N: A few months ago someone asked me if I had any plans on writing a Starwars HP crossover. I declined. Then the 7th movie approached, and I got caught up in Star Wars fever like everyone else. And so here we are. I'm not sure where I want to go with this, and this may not be updated anytime soon due to the HP/SG-1 fic I'm working on. I'm open to suggestions, so if you have a cool plot you'd like to share I'm all ears! One thing I immediately decided not to do was use the veil as an interdimensional transport. It was so overdone from what I'd read that I decided to go another route. Something unique. Of course, I haven't read all the works out there but I'm confident no one has compared Hoth to an Ice age Earth.