Today, England’s royal family calls Buckingham Palace home. But a thousand years ago, they lived on the River Thames in what was called the Palace of Westminster. Over the centuries, that palace of monarchs evolved to become this building and the center of modern Britain’s democracy.

It started when representatives of local communities—or “commons”—gathered here to be near their king. Eventually, they began meeting independently as the House of Commons, or Parliament. And to this day, Britain is ruled from right here: the Houses of Parliament.

Visitors are welcome to queue up for a free look at today’s democratic process in action.

Your visit starts with a stroll through the majestic building itself. Westminster Hall, surviving for over 600 years, was at one time the grandest hall in all of Europe.

At first it was a glorious throne room, the heart of the palace. Imagine the king ruling as a divine monarch, presiding from the far end—dispensing justice, welcoming ambassadors, and hosting boisterous banquets.

The self-supporting oak hammer-beam construction—an ingenious network of braces and arches creating a longer span with shorter pieces of wood—survives from 1397.

Just down the richly ornamented hall, the public is welcome to witness the Parliament in action. This is where the leading politicians of England, in either the uppity House of Lords or the rowdier House of Commons, have gathered for centuries.

While Westminster Hall is original Gothic, like much of the most medieval-looking architecture in Europe, the exterior of the Houses of Parliament is actually over-the-top faux-medieval. It’s Neo-Gothic, from the 1800s—the age of Queen Victoria. With prickly spires, stained glass, and church-like pointed arches, Victorian England reaffirmed both its royal and Christian medieval roots.

The famous bell tower is also Neo-Gothic. People call it Big Ben, but it’s actually the Queen Elizabeth Tower. Ben is the famous 13-ton bell behind the clock.

Just across the street from Big Ben is Westminster Abbey. This most historic church in the English-speaking world is where kings and queens have been crowned, married, and buried since 1066. While it was first built in the 11th century, much of what we see today is 14th century. When there’s a royal wedding, coronation, or funeral, the world looks on as, amid all this splendor, Britain’s glitterati gather under graceful Gothic arches.

The centerpiece is the tomb of Edward the Confessor, who founded the Abbey. And surrounding Edward are the tombs of 29 other kings and queens. This is the tomb of Queen Elizabeth I. Her royal orb symbolizes that she was queen of the entire globe.

The Abbey is filled with the remains of people who put the “Great” in Britain — saints, musicians, scientists, and soldiers. For lovers of English literature, strolling through Poets’ Corner can be a pilgrimage in itself.

The Lady Chapel, with its colorful windows and fanciful banners, has the festive air of a medieval pageant. The elaborate ceiling is a fine example of fan vaulting—a style that capped the Gothic age. At the far end, a wall of modern stained glass marks the Royal Air Force Chapel. It honors the fighter pilots of all nations who died defending Britain in 1940. With saints in stained glass, heroes in carved stone, and the remains of England’s greatest citizens under the floor stones, Westminster Abbey is the national church and the religious heart of England.

In the 1500s, King Henry VIII moved to an enormous new royal palace that once stood here. The biggest palace in Europe in its day, it stretched all the way from Big Ben to Trafalgar Square, at the end of this street.

While that palace is long gone, its name survives: Whitehall—today, Britain’s most important street. The British Empire, which once ruled nearly a quarter of the world’s population, was managed from here. A Whitehall Walk, passing Britain’s version of the Pentagon, is filled with reminders of Britain’s proud and hard-fought history. Stately reliefs, war heroes on pedestals, and stern buildings seem to celebrate the empire upon which the sun “never set.”

As it has for centuries, the Royal Horse Guards cavalry still keeps the royal family safe. And if you’re here at the right time, you’ll enjoy the ritual changing of this guard as well.

Britain’s prime ministers have long lived and worked on Whitehall at the famous and carefully guarded address, 10 Downing Street. And one of the greatest was Winston Churchill, remembered here with the iconic trench coat he wore leading his country through the dark days of World War II.

Deep under the halls of government, you can visit the Churchill War Rooms. This was the secret underground nerve center of the British government’s fight against the Nazis, even as German bombs rained down on London during the Blitz. Shut down after victory in 1945 and ignored for decades, these war rooms are open today as a fascinating time warp for visitors to explore. Audioguides give it meaning.

Audioguide: On the morning of the 16th of August 1945, the day after V-J Day and the end of the war, the map officers tidied their desks, switched out their lights for the first time in six years, and went home. And that’s the way the room stayed.

You’ll see the room where Churchill famously took his short naps. In this room, the progress of the entire war was followed as the day-by-day movement of troops and convoys was charted. And this room was the communication hub from where Churchill maneuvered Britain to ultimate victory.

The adjacent museum introduces you to Churchill, the man. It brings the colorful statesman to life—complete with his trademark cigar, bow tie, cognac—he loved his drink—and famous bowler hat. You’ll get a taste of Winston’s irascibility, wit, work ethic, even the industry of kitschy knickknacks he inspired.

Back out on Whitehall there are more monuments—this one built to remember the fallen from World War I, and this one to honor the seven million women who volunteered in World War II. Whitehall spills into Trafalgar Square, with its memorial to perhaps the greatest English war hero of all time: The one-armed, one-eyed, and one-minded Admiral Horatio Nelson, looking boldly out to sea.

The year was 1805. Napoleon, with his grand French army, was poised just on the other side of the English Channel, preparing to invade. Meanwhile, a thousand miles to the south, off the coast of Spain, Admiral Nelson defeated the French fleet at the Battle of Trafalgar. Napoleon was stopped…and Britannia ruled the waves.

Bronze battle reliefs made of melted-down French cannon decorate the column. And these huggable lions are a hit with kids.

Trafalgar Square is a vibrant people zone. It’s where Londoners gather to enjoy concerts, cheer their national team, to kick off a political demonstration…or just enjoy the fountains and a sunny day.