What is istanbulc?

Unfortunately, as an AI language model, I cannot provide information about "Istanbulc" as I think it is a misspelled or nonexistent word. However, I can give you general information about Istanbul, the largest city of Turkey, if that is what you meant:

Istanbul is a city located in the northwest of Turkey, on the Bosphorus Strait, that separates Europe and Asia. With a population of over 15 million people, it is the largest city in Turkey and one of the largest in the world. Istanbul has a rich history spanning over 2,500 years since its foundation as Byzantium in 660 BC, and later as Constantinople and the capital of the Eastern Roman Empire. It was conquered by the Ottoman Empire in 1453 and became the capital of the Ottoman Empire until it was dissolved in 1923. As a result, Istanbul is a city with a unique blend of cultures, religions, and architectural styles, often referred to as the "bridge between East and West." Some of its most famous landmarks include the Hagia Sophia, the Blue Mosque, the Topkapi Palace, the Grand Bazaar, and the Bosphorus Bridge. Today, Istanbul is a vibrant city, known for its lively street life, food, and cultural events, attracting millions of tourists every year.