Day 1: Nyhavn and The Little Mermaid

1. Morning: Start your day at Nyhavn. Take a boat tour and explore the colorful harbor.
2. Afternoon: Visit the Amalienborg Palace and the iconic Little Mermaid statue.
3. Evening: Enjoy dinner in one of the restaurants along Nyhavn.
   

Day 2: Tivoli Gardens and National Museum of Denmark

1. Morning: Spend the day at Tivoli Gardens, an amusement park with a historic charm.
2. Afternoon: Explore the National Museum of Denmark. Have lunch in the museum’s vicinity.
3. Evening: Visit the trendy district of Vesterbro for dinner and nightlife.
   

Day 3: Rosenborg Castle and Freetown Christiania

1. Morning: Visit Rosenborg Castle and its beautiful gardens.
2. Afternoon: Explore the unique Freetown Christiania. Have lunch in the area.
3. Evening: Wrap up your visit with a farewell dinner in the historic district of Indre By.

General Tips:

• Take advantage of the city’s extensive bike lanes. Consider renting a bike to explore the city like a local.
• Visit the Carlsberg Glyptotek for an impressive collection of art and antiquities.
• Explore the vibrant neighborhoods of Nørrebro and Vesterbro for eclectic shops and cafes.
• Visit Torvehallerne, an indoor food market, for a variety of culinary delights.
• Wander through the Tivoli Gardens at night to experience the magical atmosphere with illuminated rides and attractions.
• Explore the National Gallery of Denmark for a diverse collection of European art.
• If you have time, take a day trip to Louisiana Museum of Modern Art, located just north of Copenhagen.