After you arrive in Chicago, you will have an interview with an immigration officer who will want to make sure you do not want to stay in the US.

Once you've had your interview, hurray for Chicago! But forget the taxi and head downtown on the subway, which stops right at the airport - just follow the arrows towards the Blue Line subway to downtown. The subway will rise to the surface on your way from O'Hare Airport and offer you an unobstructed view of the big city's suburbs.Get off at Clark/Lake station, where there is a junction of different lines - and most importantly, there are escalators

Tip: If you don't want to carry change around in your pockets for the bus or elevated, consider buying a Ventra 3-day ($15) or 7-day ($20) pass, which you can use on all elevated and bus lines on the CTA network. You can find vending machines at every underground and elevated subway stop, or you can download the app. If you're like me and want to ride the elevated every day, it's worth buying one.

After you check in, you can take a walk, go to a convenience store for an American snack, or just watch TV and recharge for another day of exploring Chicago. 

Or head to the Riverwalk. This is a real gem of Chicago. As the name suggests, it's a pedestrianised area along the river in the heart of the city, surrounded on all sides by skyscrapers of different styles and colours. The Riverwalk is rightfully a favorite spot for visitors and locals alike. Grab a coffee, a drink or a bite to eat and settle down in the shadow of the towers that will tower around you like the walls of a valley.

It might surprise you, but the skyscraper wasn't invented in New York, but in Chicago. In a way, the wife of architect William Le Baron Jenney is responsible for it, who once put a heavy book on a birdcage. William was shocked that the cage could bear the weight of the book – and it occurred to him to reinforce the building with a similar metal “cage” and drive it much higher towards the heavens.

In Chicago, the most famous skyscrapers are Willis Tower (442 meters and 110 floors) and the one called 875 North Michigan Avenue, known until 2018 as John Hancock Tower (344 meters and 100 floors).

Willis Tower is right in the center and offers views from a height of 412 meters. If you don't suffer from dizziness, try the glass terraces with a glass (and therefore transparent!) floor. Under your feet, you can see the sidewalk and people the size of ants. Do you dare?

For information: the roof of Willis Tower is actually almost 30 meters higher than the officially highest skyscraper in the Western Hemisphere, One World Trade Center in New York. However, the skyscraper in New York has a high mast on the roof, which was recognized as part of the building, and so this building is officially "higher" than the sixteen-story higher Willis Tower. The world is simply not fair.

You can buy a ticket online and the price starts at 32 dollars

After you've had your fill of the bird's-eye view, head east to Michigan Avenue. Take it down Adams Street and on the right side of the street, between Wabash Avenue and Michigan Avenue, you'll find a sign that marks the beginning of the iconic American Route 66 here. Today it is covered with stickers, but another one is at the corner of Adams Street and Michigan Avenue.

Stop by Cloud Gate, a piece of modern art that resembles a bent drop of mercury. Or a bean, which is why the locals call it a bean. Its rounded, mirrored surface reflects the world around it, making it worth seeing.

And then we head north and across the river. On the north bank, stop by the neo-Gothic, 141-metre-high Tribune Tower, which until 2018 was home to the Tribune media company. There are artefacts in stone from famous buildings around the world, including a piece of the Taj Mahal, the Great Wall of China, Hagia Sophia, the Parthenon and the Angor Vat.

A few blocks away, the John Hancock Tower (let's stick with that name, it's easier to remember) rises to the sky. For the hard of hearing, for whom looking out the window isn't enough, there's also the "Tilt" - a strange window design that tilts out into space. It's almost like you're falling. But be careful when buying tickets, because the basic $35 ticket does not include the Tilt. Tickets that include the Tilt start at $44. You can buy them online here: https://360chicago.com/tickets

Tip: Get here tonight when Chicago lights up with a thousand lights and have a drink with a fantastic view.

Head to the Merchandise Mart stop (located at the building of the same name, which is so huge that it had its own zip code from its opening in 1930 until 2008). Get on the Brown Line train heading across the river (the name of the final stop doesn't matter, as the Brown Line starts and ends at Kimball Station). The train travels through the Loop, a loop of track that encircles downtown Chicago, and then heads back through the Merchandise Mart stop and on to Kimball Station, where the line begins and ends.

From the height of the second floor, you'll see the bustling streets of downtown, the beautiful ornate details on the facades of Native American skyscrapers, suburbs, homes and brick apartment buildings. 

At the Kimball stop, board the train back downtown and get off again at the Merchandise Mart (of course, you can take the scenic ride again - you don't get to experience this in the Czech Republic!). 

Go down to the road level and head across the bridge and further into the center, where you can walk through the streets inside the Loop. Trains on the elevated railway will rumble above your head every few minutes.

That's just Chicago. 

The corner of La Salle and Adams Street is worth noting, where the first skyscraper, designed by the aforementioned Mr. William Jenney, stood from 1885 to 1931. It was reinforced with steel and had a dizzying ten floors.

Don't miss the Monadnock Building on Jackson Boulevard. Architect Daniel Burnham, who, among other things, was in charge of building the site for the World's Fair in 1893 and also designed the Flatiron Building in New York, participated in its construction.

For a snack or something to drink, go to the Target store on State Street. This stop is also mainly about the building, which is the Sullivan Center from 1899. The reason is the windows. The use of steel reinforcement allowed architects to increase the area of ​​the windows to a size that had never been seen before. 

In downtown Chicago, in the Loop, there are plenty of such architectural treasures, so I can only recommend paying for a guided tour (the price is around $30). The Chicago Architecture Center organizes good ones, and their overview is here.

What do the Museum of Science and Industry and the Art Institute have in common? Both buildings were part of the World's Fair, held in Chicago in 1893 to mark the quadricentennial of the discovery of America by the explorer Christopher Columbus. The Ferris wheel, actually the Ferris wheel, was first seen during the World's Fair, because it was invented by one George Washington Ferris with one purpose in mind: to enable Chicago to top the Eiffel Tower, built for the 1889 World's Fair.

This museum is a bit out of hand, so use your Ventra ticket and get on the bus. On the bus, you'll get to know real Americans pretty up close. 

Just buy your museum tickets on the spot - there probably won't be lines like at "tourist traps" like Willis Tower or the John Hancock Center. 

Whether you prefer fact-based scientific discovery or you prefer to ride the wave of creativity, each building offers interesting exhibitions and is well worth a visit. 

For the hardened, there is the International Museum of Surgical Science. 

And if you're curious about the history of Chicago's signature drawbridges and the mechanics that make the one-ton colossi lift like anything, head to the Michigan Avenue Bridge, home of the McCormick Bridgehouse & Chicago River Museum.

You can take a walk inside the Loop, settle in on the Riverwalk, head along the shores of Lake Michigan, or maybe take another trip overhead. Just be sure to pick up a few souvenirs.

Then have one last breakfast, go to the Riverwalk and enjoy the view of the skyscrapers. 

The Blue Line will then take you to the airport.