The electric central node of Istanbul's Beyoğlu district, Istiklal (Turkish for "Independence") is a pedestrian street that runs almost 2 km from near the impressive cylinder of the Galata Tower to the city's famed modern gathering place, Taksim Square. To say that Istiklal Avenue bustles would be an understatement; it practically froths with tourists. Don't let that deter you, though. Just like Las Ramblas in Barcelona and Champs-Elysees in Paris, you'll find that much of the appeal comes from its place as a beehive of activity.
Its popularity can be attributed to an architectural heritage that hearkens back to the late 19th century, the characteristic red trams with their trilling bells that regularly part the seas of humanity, and a vast spectrum of goods and services available to the discerning public. There is quite a selection of Turkish restaurants and patisseries, while cinemas, art galleries, and the ubiquitous coffee shops only touch on what's available here. The biggest problems are that goods and services are more expensive, while the infiltration of a number of Western stores and shops tends to detract from the street's romantic appeal. Then again, if you find yourself unsatisfied (or even claustrophobic), break off down one of the many cramped side streets to seek out other small businesses. Just be careful with your belongings and keep a close eye on your surroundings.
Landmarks of note along Istiklal Avenue include the the world's second oldest subway station, Tünel, the iconic iron gates of Galatasaray Square, the 16th century Roman Catholic church of St. Mary Draperis, and the consulates of seven different nations. If Istiklal seems a bit too much like it's sold out, then try Soğukçeşme Street in the old city. It's far less lively due to its proximity to the Hagia Sophia and Topkapı Palace, but at least there is an undiluted sense of authenticity to its rows of classic Ottoman residences.
Istiklal is also quite the nightlife destination, spilling over with plenty of club and bar options and even a few gems that hide down a multitude of side streets. Machine Club and Hypnos encompass the dance music spectrum, Pendor Corner is your local rock club, and establishments like the Beatles Cafe and the James Joyce bring a whiff of familiarity that may be welcome in the wild buzz of this street. If you're searching for a variety of options, focus near Tünel Square or just east of the British Consulate.