Istanbul is a city of rich history, stunning architecture, and vibrant culture. Located on the Bosphorus Strait, Istanbul straddles both Europe and Asia and has been a major cultural and economic hub for centuries. Here are some of the top things to see and do while visiting Istanbul:

1. Visit the Hagia Sophia, a former cathedral that was later turned into a mosque and is now a museum. The building is a masterpiece of Byzantine architecture and features stunning mosaics and frescoes.

2. Explore the Grand Bazaar, a bustling market with over 4,000 shops selling everything from spices and textiles to jewelry and ceramics.

3. Take a cruise on the Bosphorus Strait, which separates Europe and Asia. You'll have the opportunity to see the city's iconic skyline and visit charming towns along the way.

4. Visit the Topkapi Palace, a sprawling complex that was once the primary residence of the Ottoman Sultans. The palace features ornate architecture, beautiful gardens, and a museum with a collection of artifacts from the Ottoman Empire.

5. Visit the Galata Tower, which offers panoramic views of the city. The tower is also home to a museum with exhibits about the history of the tower and the surrounding area.

6. Take a stroll through the Sultanahmet neighborhood, home to some of the city's most iconic landmarks, including the Blue Mosque and the Basilica Cistern.

7. Visit the Istanbul Modern, a contemporary art museum that features works by both Turkish and international artists.

8. Try some traditional Turkish cuisine at a local restaurant. Must-try dishes include kebabs, meze platters, and baklava.

9. Take a trip to the Princes' Islands, a group of nine islands located in the Sea of Marmara. The islands are a popular weekend getaway for Istanbul residents and offer a chance to escape the city's hustle and bustle.

Overall, Istanbul is a city with something for everyone. Whether you're interested in history, culture, or just want to relax and enjoy the city's many offerings, you'll find plenty to see and do in Istanbul.