Where on earth: Built on 43 hills and just 49 miles square, San Francisco, on America's West Coast, is California's most liberal city. From hippies to high rollers its laid-back vibe, cool bars and vibrant restaurant scene make it hard for anyone not to leave their heart in San Francisco.
What to see: Think of San Francisco and its iconic Golden Gate Bridge springs to mind, so it's a given that you have to check it out. I walked, but you can also cycle, across the bridge to the viewing point on the north side for exceptional vistas of the city. San Francisco is relatively compact, making it pretty walkable. If, like me, you're not a fan of steep hills (San Francisco is where you'll find Lombard Street, the world's most crooked street) you can hop on a cablecar to get around town.
Another of San Francisco's most recognisable landmarks is Alcatraz. The infamous prison once housed some of America's most notorious gangsters including Al Capone. Alcatraz Cruises run night tours of 'The Rock' and after watching the sun set across the Golden Gate Bridge it's more than a bit spooky hearing tales of the inmates after dark. You'll need to book though as the tour is only open to a limited number of visitors every evening. At Fisherman's Wharf I saw a totally different side to San Francisco, it reminded me of Blackpool, but it's worth braving the tourists for the Dungeness crab stalls.
Where to shop: Union Square is literally heaving with every kind of shop you can possibly think of including a Westfield Shopping Centre with 200 shops and restaurants. From the classic American department stores of Macy's, Bloomingdale's and Saks, designer shops including Prada, Bulgari and Cartier to high street shops such as Forever 21 (it's massive) and Old Navy (think Primark meets Gap) there's something to suit all budgets. Luckily I didn't have enough time to do too much shopping. I'd have done some serious damage to my bank balance if I had.
When it comes to food, Mission is the district to go to for eating out. Start the day with breakfast at Craftsman and Wolves pattisserie where you'll be spoilt for choice by the cookies, croissants (they even do a root veg variety) and cakes on offer. Mission is also home to Foreign Cinema one of San Francisco's finest restaurants. It's a good place for celeb spotting stars like Neil Patrick Harris and KD Lang. Opt for outdoor seating (there are heaters) in this quirky restaurant and you can watch world cinema and classic movies screened on the wall while you tuck in to some of the city's finest contemporary cuisine. The menu changes daily – my favourite dish was a starter of house-cured sardines with roast potatoes, pickled onions and dill crème fraîche. Portions are generous so don't forget to leave room to squeeze in dessert. I was there for dinner but if you get the chance to try it, the weekend brunch at Foreign Cinema is said to be legendary, they even serve posh pop tarts filled with pineapple or Anjou pear.
Where to party: Happy hour at the Tonga Room a kitsch tiki bar that's part of the Fairmont Hotel is a great way to get the night started. Complete with its own ship's mast, thunder and tropical storms (it's quite weird when you hear the sound effects kick into action), there's even a waterfall and floating band (they don't come on stage until 8pm) to add to the cheese factor.
If getting glammed up and making an entrance is more your thing then Slide nightclub is the perfect place for late night drinking and dancing. This speakeasy is on the site of what was once Coffee Dan's, one of San Francisco's most famous prohibition bars. As its name suggests the way in is via a long slide, which is brilliant fun. Just make sure you're wearing trousers or you won't be allowed down it. Valencia Street in the Mission district is also packed full of cool dive bars and trendy watering holes such as Zeitgeist. Or you can always pop next door to the Foreign Cinema's adjacent bar Lazlo.
Where to stay: The guide books will tell you to head to Coit Tower for panoramic views of San Francsico. Currently, it's closed for renovation, but you won't care if you're staying at the Mandarin Oriental San Francisco. Located in the Financial District, in the third tallest building in the city, it's close to all the action downtown. It's easy to see why Lady Gaga checked into this hotel on in a recent visit to San Francisco. Rooms are neutrally decorated as it's the views that take centre stage. And all I can say is wow, are they impressive.
I arrived at night and was treated to a twinkling display of the metropolis all lit up from our room on the 48th floor (the top floor of the hotel). And while it was a struggle to drag myself out of my incredibly comfy king-size bed it was worth an early wake up call to see the pink glow of the sunrise slowly spreading across San Francisco skyline. As the sun came up I could clearly see both the Golden Gate Bridge and Alcatraz from the window of my luxurious room.
Top tip: If you're in Mission during the daytime keep an eye out for the street art. You'll find murals from underground artists dotted around the district that would give Banksy a run for his money.
Do it! Cosmo travelled to San Francisco with Travelbag, Brand USA Discover America and Visit California. A five-night stay with Travelbag at the Mandarin Oriental San Francisco starts from £1,689 pp, room-only, including flights with United Airlines from London Heathrow. See San Francisco Travel for more info on the city.