Every first visit to Prague follows the same loop: wait for the Astronomical Clock to chime, shuffle across Charles Bridge, climb to the castle, buy a trdelník you'll later learn isn't even Czech. It's a fine loop, and you should do it once. But this city keeps its best material one layer down — sometimes literally, because the most unusual things to do in Prague start below the pavement, in a flooded medieval underworld most visitors never hear about. This guide covers five genuinely strange experiences you can actually book: an underground boat ride, a WW2 assassination walk, a five-hour Kafka pilgrimage, a pub crawl that ends at a clifftop fortress, and a tour of Tom Cruise's Prague.
Why Prague's Strangest Sights Are Under Your Feet
Old Town's street level is not original — it's a medieval engineering project. After the Vltava flooded the city once too often, Prague raised its streets in the 13th century, in places by several meters, and the ground floors of Romanesque houses became cellars overnight. The result is a second, older city under the first one: vaulted rooms, walled-up passages, and waterways running beneath buildings that look perfectly ordinary from the square. Most of it is sealed off or privately owned, which is exactly why the few legitimate ways in are worth knowing about.
Sail the Underground: A Boat Ride Below the Streets
The strangest booking you can make in this city is Flouting in Prague underground — yes, "flouting," a charmingly garbled translation of "floating" — a 3-hour trip that puts you in a boat beneath the streets, from $178.25. You descend below modern Prague, climb aboard, and drift through stone passages by lamplight while a guide explains how an entire layer of the city ended up underfoot and underwater. Your phone camera will struggle down there, which is part of the appeal: this is one of the few Prague experiences you can't spoil for yourself on Instagram beforehand.
Two practical notes. Cellar temperatures hold steady and cool all year, so bring a layer even in July. And capacity is capped by the boats themselves, so reserve this one before you land, not after — it's the most expensive tour on this list, and the one people are still talking about a year later.
Operation Anthropoid: The Story Most Visitors Never Hear
In May 1942, two Czechoslovak paratroopers trained in Britain — Jozef Gabčík and Jan Kubiš — ambushed Reinhard Heydrich at a sharp tram bend in the Libeň district. Heydrich wasn't a mid-level functionary: he ran occupied Bohemia and Moravia and had chaired the Wannsee Conference that planned the Holocaust only months earlier. Gabčík's Sten gun jammed at point-blank range; Kubiš threw a converted anti-tank grenade that tore the staff car apart; Heydrich died of his wounds about a week later, the highest-ranking Nazi killed by resistance fighters in the entire war.
The World War 2 Prague Tour: Operation Anthropoid (from $117.64, 3 hours) walks the story where it happened, ending at the Church of Sts. Cyril and Methodius on Resslova Street. Betrayed by one of their own, the paratroopers made their last stand in the church crypt weeks after the attack, and the bullet-pocked wall around the crypt's ventilation slit still faces the street. The crypt itself is now a national memorial — check current opening hours if you want to go inside afterward, and you will want to. If you've seen the film Anthropoid, this is the real geography; if you haven't, you'll leave needing to watch it.
Kafka's Prague, All Five Hours of It
Franz Kafka was born a few steps from Old Town Square in 1883 and barely left. He reportedly once traced a small circle over a map of the Old Town and said it enclosed his entire life — school, university, office, all within a few blocks of each other. That makes Prague one of the only cities where you can walk a major writer's complete world in a single outing, and the Franz Kafka: Tour of Prague takes the full five hours to do it properly, from $117.64.
The route logic is the man's biography on foot: his birthplace beside St. Nicholas Church, the Jewish Quarter that shaped his family's world, the insurance office where he processed industrial accident claims by day and resented it by night, and Golden Lane up at the castle, where he wrote in his sister's tiny house. You'll also pass David Černý's giant rotating mirrored Kafka head near Národní třída, the strangest literary monument in Europe. Five hours is a real commitment — eat first, wear actual shoes. If that's more Kafka than you signed up for, there are plenty of shorter walking tours in Prague to choose from.
Pub by Pub Up to Vyšehrad
Vyšehrad is the fortress Prague keeps for itself. It sits on a rock above the Vltava south of the New Town — legend says Princess Libuše stood here and prophesied a city whose glory would touch the stars — and it delivers the twin spires of the Basilica of Sts. Peter and Paul, ramparts with the best upstream river views in the city, and the national cemetery where Dvořák, Smetana, and Mucha are buried. What it doesn't have is the castle district's crowds.
The Pub Tour to Magical Mountain Vyšehrad (from $82, 3 hours) treats the fortress as something you drink your way toward, stopping at neighborhood pubs where beer costs what beer should cost in the Czech Republic — often less than bottled water. It's the cheapest tour on this list and the most sociable, and it works best on your first evening, when you want orientation, calories, and Czech pub etiquette explained by someone who actually uses it.
The Mission: Impossible Detour
Brian De Palma shot the first Mission: Impossible here in the mid-1990s, with Prague playing itself: the embassy reception filmed inside the National Museum, the aftermath on Charles Bridge, the lamplit corners of Kampa Island. The Mission: Impossible Tour in Prague (from $142.60, 4 hours) connects the locations with the production stories, and it doubles as a covert greatest-hits walk — you cover a surprising amount of riverfront Prague while debating whether the NOC list plot ever made sense. It didn't, and that's fine.
How to Stack These Without Wrecking Your Trip
With two free days beyond the standard circuit, pair the Anthropoid walk in the morning with the Vyšehrad pub tour that evening — heavy history, then beer, is a reliable sequence — and give the underground boat its own slot the next day. With four days, add Kafka, but let those five hours own the whole day; a long literary walk shares badly with anything else. The two story-driven walks cost the same from $117.64, so if you're choosing just one, choose by temperament: Anthropoid is gripping and heavy, Kafka is wry and meandering.
Summer slots vanish fastest on the small-capacity tours — the boat above all — so book that one first and leave the pub crawl flexible. If none of these five fits your dates, browse the rest of the adventure tours in Prague or the full lineup on our Prague destination page. The Astronomical Clock will still be doing its thing at the top of every hour. It can wait.
Frequently asked questions
Is the Prague underground real, and can you visit it?
Yes. Old Town's street level was raised in the 13th century to fight Vltava flooding, which buried the original ground floors of Romanesque houses and created a layer of cellars, passages, and waterways beneath the modern city. Most of it is sealed off or privately owned, so guided tours are effectively the only way in — including one that explores the flooded sections by boat.
What happened during Operation Anthropoid in Prague?
In May 1942, Czechoslovak paratroopers Jozef Gabčík and Jan Kubiš, trained in Britain, ambushed and fatally wounded Reinhard Heydrich, the Nazi ruler of occupied Bohemia and a chief planner of the Holocaust. Weeks later, after being betrayed, the paratroopers died in a siege at the Church of Sts. Cyril and Methodius on Resslova Street. The crypt where they made their last stand is now a national memorial, and the bullet-scarred wall is visible from the street.
Is Vyšehrad worth visiting compared to Prague Castle?
Not instead of the castle — in addition to it. Prague Castle has the scale and St. Vitus Cathedral, but Vyšehrad offers freely walkable grounds, far thinner crowds, the national cemetery where Dvořák and Smetana are buried, and arguably better views over the Vltava. Locals treat it as a park, and most tourists skip it entirely, which is exactly the point.
How many days do you need in Prague to get beyond the main sights?
Three full days is a realistic minimum: one for the classic circuit of the castle, Charles Bridge, and Old Town, and two for the stranger layer — an underground or WW2 tour plus Vyšehrad or another themed walk. With four or five days, you can add a longer deep dive like a five-hour Kafka walking tour without rushing anything.