Germany is awash with beautiful buildings and amazing architecture but it also contains fascinating relics of its ancient and recent history and some very weird properties. From upside-down houses and the world’s narrowest alleyway to a steeple under a lake and an extraterrestrial church, this collection of oddities will make you look twice.

Click or scroll through to discover Germany’s amazing architectural mysteries...

This memorial was completed in 1913 and commemorates the Battle of the Nations. The body of water in front of the Napoleonic war memorial is known as the Lake of Tears. It was designed to remind visitors of the tragic loss of life from the unified armed forces of Russia, Prussia, Austria and Sweden, who fought Napoleon and his allies on the German plot just over two centuries ago.

Not your typical monument to the fallen, this Lord of the Rings-style building is as intriguing on the inside as it is out, with its echoey crypt chambers containing large stone figures with colossal faces and closed eyes. Eight colossal medieval knights stand as silent tributes to fallen warriors, joined by the enigmatic "Guards of the Dead".

Ascend to the second level, known as the Hall of Fame, and you'll encounter four more giants, each an impressive 31 feet tall. Feeling adventurous? Conquer the 500-step climb and emerge onto the roof deck, where a breathtaking panorama awaits – a poignant reminder of the city's history and the sacrifices made to protect it.

Most days of the year, this advent calendar-like church appears as this steel-glass cube, but the Herz-Jesu-Kirche (Church of the Sacred Heart of Jesus) in the Neuhausen district of Munich comes with an impressive party trick...

On high feast days the doors – the largest church doors in the world – swing open to reveal the wooden church within. The glass front is also covered with nails that spell out quotes from the bible in a specially developed code. Not many places of worship are as cryptic as this one.

Germany’s capital has quite a reputation for its airports, but this abandoned building serves as a reminder of one of the country’s darkest periods. Known as ‘Hitler’s airport’, the Tempelhof Airport complex was officially opened in 1923, but the airport building itself was replaced in the Nazi era. 

The vast terminal building was once among the world's largest and its limestone facade would have gleamed white in the sunlight. The innovative cantilevered roof, supported by a complex system of pillars, sheltered passengers from the elements and maximised aircraft handling.

Seen from above, the floor plan was designed to look like an eagle’s outspread wings and images of the bird can still be found in and around the abandoned building today. It remains one of the world’s largest buildings, at 3.2 million square feet. Though originally planned to be even larger, construction limitations left parts incomplete, creating an intriguing mix of finished and unfinished sections, each with their own story to tell.

This intriguing creation only caught archaeologists’ eyes in 1991, when the German government photographed the town of Goseck and noticed something strange. More than a decade later, they realised what they were looking at was the remains of an ancient solar observatory, which has since been declared the world’s oldest.

Dubbed the 'German Stonehenge', the walled compound is constructed of concentric rings of tall wooden palisades and the southern gates are thought to mark winter and summer solstices, according to astro-archaeologist, Wolfhard Schlosser. Remnants of ritual fires and human bones suggest the spot was also used for sacrifices long ago, and the site has been dated to between 4800–5000 BC.

This church makes up part of the cliff in Idar-Oberstein. Rumour has it the holy building was built after a jealous man murdered his brother, the prince, and wanted to repent for his sins. While there’s no evidence to back up this tale, the cavern’s geographical history is clear to see – a natural spring, bursting out of the cliff, carved out the cavern in which the church sits. 

At the top of the cliff lies the ruins of a castle-fortress, Bosselstein. At the end of the 20th century, a tunnel was built through the rock to the entrance of the church. Idar-Oberstein is a gemstone town, and this architectural marvel certainly counts as one of its sparkliest gems. The town also happens to be the birthplace of Bruce Willis.

Architectural mysteries come in all shapes and sizes, including enormous versions of beloved characters from Star Wars. The likeness of this hilltop university observatory to R2-D2 isn’t a coincidence – the 2018 renovation of the already-existing observatory was led by Dr. Hubert Zitt, a huge fan of the franchise. Zitt enlisted his students to help with this sensational sci-fi creation, which reportedly, took 120 hours to paint. 

Remarkably, this isn't the first building of its kind to be painted to resemble R2-D2, as the Goodsell Observatory in Minnesota was transformed into the friendly droid back in 2010.

The building itself is a small public observatory, which is used for tours and showings rather than university research, not to mention a popular tourist attraction for Star Wars fans. 

Home to a mysterious alchemist in the 1600s, Castle Frankenstein – Burg Frankenstein in German – may have inspired Mary Shelley’s Gothic novel of the same name.

The original mad scientist was Johann Konrad Dippel, who was thought to dabble in potion-making, electrical therapies and ghoulish experiments with body parts stolen from neighbouring graveyards. 

Today the hilltop castle overlooking the city of Darmstadt is ruined, with only two towers, a restaurant and a chapel still intact, but it remains a popular tourist spot thanks to its literary links.

From late October to early November, the Burg Frankenstein Halloween party attracts visitors dressed as ghosts, vampires, werewolves and witches for various spooky-themed events.

The city of Reutlingen is home to the 'narrowest alley in the world', which was officially entered into the Guinness Book of Records in 2007. Spreuerhofstraße measures just 12.2 inches at its narrowest point and just shy of 20 inches at its widest. 

The street is thought to be getting even narrower, as one of the adjacent buildings is slowly leaning into the passageway. While not exactly spacious now, if the street becomes too small to allow anybody through, it would lose its status as the world’s narrowest alley.

Changing climates can reveal a whole host of curiosities and in the hottest months, the remnants of a charming church in Waldeck rear their head. The church was sunk underwater when the village surrounding it was flooded in 1914 to make way for a nearby reservoir's overflow basins.

For years, the exact location of this tiny building was a mystery and misreporting in various newspapers led many on a wild goose chase. 

During dry months, visitors have flocked to Edersee to try to spot the church among the reemerged foundations of the old village – a church that was never really there in the first place! To celebrate the anniversary of the reservoir, the local village built a replica of the original church above water for everybody to see.

As impressive as towers often are, they can be found all across Germany. But how about a half-tower? In Lübeck, there is a half-timbered house built into a segment of medieval wall. The tower house was built in 1672 by a clever architect who took advantage of the hollow tower segment. 

The somewhat wonky combination makes for a unique piece of architecture, standing at a slant in one of the country’s most picturesque towns. The 13th-century wall that curves around the house previously stretched along the whole street, aptly named An der Mauer – meaning 'on the wall' – until most of it was torn down in 1884.

There’s an extraterrestrial energy about the Brother Klaus Field Chapel in Mechernich, which was completed in 2007. The construction of the building was simple, with 112 tree trunks leaning together like a teepee forming the foundations. Concrete was then used to build the sharp, blocky exterior and the internal logs were burnt away to leave the wood's impressions.

The triangular door was the final, and perhaps most striking, touch, along with a poured molten lead floor. There is no electricity, so all of the chapel’s light comes from a hole at the top of the building, where the tree trunks originally met, and from stainless steel pipes set into the wall.

An incredible 92,000 gallons of water flow through the 300-year-old hydropneumatic system behind Bergpark Wilhelmshöhe in Kassel. The action starts at Europe’s largest hillside park at the 350-metre Grand Cascade, which streams down from an octagonal building topped by a pyramid and a statue of Hercules.

Water then gushes into waterfalls and rapids to the Grand Fountain. Along with the exciting waterworks, the park has a Chinese pagoda and faux ruins. Begun by Landsgrave Carl of Hesse-Kessel in 1689, the Bergpark – or 'mountain park' – was developed further into the 19th century. Perhaps unsurprisingly, it was designated a UNESCO World Heritage Site in 2013.

Here's another waterpark – but this one is considerably creepier than its Baroque counterpart. Spreepark in Berlin hasn’t been up and running since 2002, but it still harbours remnants of the old theme park, with rusty roller coaster tracks, life-size dinosaur statues and children's rides that would’ve been cute, once upon a time.

The park has a controversial past, including a drug-smuggling owner and visitor numbers quickly shrivelled at the start of the noughties. Its creepiness has been put to good use, though. Spreepark is a popular film set and large portions of the movie Hanna were filmed there.

Pisa is known for its tower's iconic lean, but the Suurhusen church in Hinte also has some seriously wonky walls. The late medieval steeple was once the most tilted tower in the world, leaning at an angle of 5.19 degrees, while Pisa is only 1.22 degrees. Sadly, it lost the record in 2010 to Capital Gate in Abu Dhabi, but it’s still an impressive sight.

The church is thought to have been built completely upright, but it was constructed on marshy land on the foundations of oak tree trunks. The land drained in the 19th century and the wood rotted, causing the church to tilt. Safety concerns prompted the church to be closed to the public in 1975, but it reopened a decade later, following significant stabilisation efforts.

This was the first of two upside-down houses in Germany. Built in 2008, the only element that hasn’t been turned on its head is the outside stairs that lead to the attic. Polish architects Klaudiusz Golos and Sebastian Mikiciuk designed the home, which was made to give visitors a new perspective on everyday living, with tourism very much in mind. 

Inside, the house becomes even more bizarre. All of the furniture and fittings are above you, with sofas, potted plants and even a toilet looking as though they’re defying gravity. Even decorative touches like the paintings and curtains are flipped.

In 2010, a second upside-down house – Haus Kopf-über – came to Germany on the island of Rügen. Like its predecessor, it isn’t just the exteriors that are turned on their heads, as all of the furniture is also attached to the ceiling. 

The outside of the house also comes with a variety of homely touches, such as a bike, bench and BBQ, all attached to what would be the house’s porch. Visitors to both optical illusion houses are encouraged to head inside and take superhero-style photos in the misaligned rooms.

This amphitheatre was one of around 45 outdoor settings designed to host Nazi propaganda presentations in the 1930s. The locations were chosen for their historical importance and this one was built on Heiligenberg, or ‘Holy Mountain’, which had attracted religious groups and cults for centuries. 

The amphitheatre covers 82 feet of sloping land and two hexagonal towers to hold flags, lighting and speakers. At its opening, 20,000 people turned out to hear Joseph Goebbels speak, but the location didn’t prove as popular as initially hoped. The site was turned into a public park and remains a much-visited spot today. 

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