Istanbul, a captivating city that bridges the gap between Europe and Asia, boasts a rich blend of history, culture, and modernity. Here's a concise summary of the information you provided:

Istanbul is situated in the north-western part of Turkey, spanning both sides of the Bosphorus Strait. This strategic location connects the Black Sea to the Sea of Marmara and serves as the boundary between Europe and Asia in Turkey. The city is home to approximately 14.8 million residents, making it Turkey's largest and the 7th largest city globally. Istanbul offers a diverse range of experiences, from contemporary business districts and high-end shopping to ancient historical sites, cultural landmarks, enchanting bazaars, and stunning mosques filled with exotic goods.

Worth seeing 
Sultanahmet District: This historic area on the European side is home to Istanbul's prominent sights. Notable attractions include the Blue Mosque, known for its blue-tiled interiors, and the Hagia Sophia, an architectural marvel with intricate mosaics and a rich history.

Basilica Cistern: Located in the same district, the Basilica Cistern is an impressive subterranean structure that once stored the city's water reserves. Modern lighting enhances its unique atmosphere.

Climate
Istanbul experiences a warm Mediterranean climate. Summer temperatures typically range from 25 to 30 degrees Celsius, offering pleasant warmth. Winters are relatively cool, with temperatures ranging between 5 and 10 degrees Celsius.

Currency
Turkish Lira (TRY)

Travel guides
Official site for tourists:www.english.istanbul.gov.tr 

And for those who can't get enough, these sites are also well worth a visit:

www.visitistanbul.org 

www.istanbul.com

http://www.istanbulcityguide.com