Bilbao is a beautiful city in the Basque Country of Spain, known for its stunning architecture, delicious food, and rich culture. Here's an ideal itinerary for 3 days in Bilbao:

Day 1:

• Start your day with a visit to the Guggenheim Museum, one of the most iconic landmarks in Bilbao. The museum is known for its unique architecture and impressive collection of contemporary art.
• After exploring the museum, head to the Casco Viejo (Old Town) neighborhood for lunch. This area is full of charming streets, historic buildings, and delicious pintxos (Basque tapas).
• In the afternoon, take a stroll along the riverfront and enjoy the views of the city. You can also visit the Zubizuri Bridge, a pedestrian bridge designed by Santiago Calatrava.
• For dinner, head to one of the many Michelin-starred restaurants in Bilbao, such as Azurmendi or Etxanobe.

Day 2:

• Start your day with a visit to the Mercado de la Ribera, one of the largest indoor markets in Europe. Here, you can sample local cheeses, meats, and seafood, and pick up some souvenirs to take home.
• After the market, head to the Basque Museum, which showcases the history and culture of the Basque Country. The museum is located in a beautiful 17th-century building and has exhibits on Basque language, music, and art.
• In the afternoon, take a funicular up to the top of Mount Artxanda for panoramic views of the city. You can also enjoy a picnic or a drink at one of the cafes on the mountaintop.
• For dinner, head to one of the many traditional Basque restaurants in the city, such as Asador Etxebarri or Elkano.

Day 3:

• Start your day with a visit to the San Mamés Stadium, home of the Athletic Bilbao football team. You can take a tour of the stadium and learn about the history of the team and the sport in the Basque Country.
• After the stadium, head to the Alhóndiga Cultural and Leisure Center, a former wine warehouse that has been converted into a modern cultural center. Here, you can enjoy art exhibits, movies, and concerts, or relax in the rooftop pool.
• In the afternoon, take a day trip to the nearby town of Getxo, known for its beautiful beaches and historic mansions. You can also visit the Puente Colgante (Hanging Bridge), a UNESCO World Heritage Site that connects Getxo to the neighboring town of Portugalete.
• For dinner, head back to Bilbao and enjoy some more pintxos in the Casco Viejo neighborhood.

I hope this itinerary helps you plan your trip to Bilbao! Let me know if you have any other questions or need more recommendations.