London

Here's an ideal itinerary for 3 days in London:

Day 1:

• Start your day with a visit to the iconic Tower of London. This historic castle has served as a royal palace, prison, and even a zoo over the centuries. Be sure to see the Crown Jewels and take a guided tour with one of the Yeoman Warders.
• After the Tower, head over to the nearby Tower Bridge. You can walk across the bridge and enjoy the views of the Thames River and the city skyline.
• For lunch, head to Borough Market, one of London's oldest and most famous food markets. You'll find a wide variety of delicious food options here, from fresh seafood to artisanal cheeses.
• In the afternoon, visit the British Museum. This world-renowned museum has an incredible collection of artifacts from around the world, including the Rosetta Stone and the Elgin Marbles.
• End your day with a visit to the West End, London's theater district. Catch a show at one of the many theaters in the area, or just stroll around and take in the lively atmosphere.

Day 2:

• Start your day with a visit to St. Paul's Cathedral. This stunning cathedral has been a symbol of London for over 300 years, and its dome is one of the city's most recognizable landmarks. Be sure to climb to the top of the dome for incredible views of the city.
• After St. Paul's, head over to the nearby Tate Modern. This modern art museum is housed in a former power station and has an impressive collection of contemporary art from around the world.
• For lunch, head to the nearby Southbank Centre Food Market. This outdoor market has a wide variety of food stalls, from Indian street food to gourmet burgers.
• In the afternoon, visit the Houses of Parliament and Big Ben. You can take a guided tour of the historic buildings and learn about the history of British democracy.
• End your day with a visit to the London Eye. This giant Ferris wheel offers incredible views of the city, especially at sunset.

Day 3:

• Start your day with a visit to the British Library. This massive library has an incredible collection of books and manuscripts, including original copies of the Magna Carta and Shakespeare's First Folio.
• After the library, head over to the nearby Camden Market. This eclectic market has a wide variety of stalls selling everything from vintage clothing to street food.
• For lunch, head to Brick Lane, one of London's most famous food streets. You'll find a wide variety of delicious food options here, from Indian curries to bagels.
• In the afternoon, visit the National Gallery. This world-renowned art museum has an incredible collection of paintings from the 13th to the 19th century, including works by Leonardo da Vinci, Vincent van Gogh, and Rembrandt.
• End your day with a visit to Buckingham Palace. You can watch the Changing of the Guard ceremony and see the home of the British monarch.