1 Chandni Chowk
Get up close and personal with the sights and sounds of everyday Calcutta with a walk (or jostle) through Chandni Chowk Lane, a crazy multitude of small streets leading to Central Avenue. The area is lined with shops and stalls selling everything from dog collars to Alfonso mangoes. The crowds prevent cars from entering, but auto-rickshaws still get through, honking at ear-splitting levels. You'll also hear Hindi film music blaring from loudspeakers on hawker carts, the Muslim prayer call from the nearby mosque, and plenty of ribald local language. The best time to visit is mid-morning on weekdays. Avoid the evening rush hour.
You can't visit Calcutta and not stroll down Park Street, the poshest address in the West Bengal capital. Old Calcuttans still talk of the 'good old days', when the tea room served English afternoon tea. You won't find cucumber sandwiches or jam-filled scones any more, but you can still get a passable Danish pastry, fruitcake and cups of Darjeeling tea for about HK$15. Try getting a seat near the tinted-glass front for a view of life in Calcutta's fast lane (closed Mondays, tel:  33 2229 7664).
3 Auction houses
The auction houses on Russell Street, off Park Street, are a legacy of Calcutta's 'Brown Sahib' colonial past. Visit on a Sunday afternoon and you can catch the excitement of bidding for anything from nouveau-riche furniture to old enamelware. Suman's Exchange, Russell Exchange and Modern Exchange attract a small group of faithful regulars, and auctions usually begin at 1pm, so arrive earlier to check out what's on offer. If you're lucky, you could walk away with antique silver cutlery or an ivory chess set for a song.
4 Open-air 'Chinese' breakfast
A single street in the city's central wholesale market, marked by a parking lot, is where Calcuttans go for their Chinese breakfast fix. Originally run by Chinese settlers, now the hot mo mo (potstickers), gao chi bao (meat-filled buns), sweet bread fritters and steamed prawn and fish dumplings are mostly made by the city's small Tibetan population. To get there, head for Poddar Court (a landmark on Tiretti Bazaar Street) and ask for directions to the 'Chinese food shops', about a five-minute walk away. For less than HK$10, you can eat your fill, but get there early because everything is usually sold by 7am.
Located in the south of the city, Kalighat, or Kali Temple, is home to Calcutta's principal deity, Kali, the most bloodthirsty Hindu goddess. The temple was built about 200 years ago by the Sabarna Roy Choudhurys, a philanthropic Bengali Brahmin family. A typical Indian 'temple street' leads up to the temple, with bright stalls selling everything required for daily worship: bells, flowers, fruits, sweets, coconuts, incense sticks and miniature clay idols of deities. As far as temple architecture goes, Kalighat is unimpressive, but a visit is an opportunity to see how this dark goddess is worshipped. Strong-stomached visitors can check out the bloodstained grounds - Kali destroys to create, and is frequently propitiated by animal sacrifice. You can also get a closer look at the fearsome Kali iconography - her blood-red tongue lolling out, her body painted black and naked bar a garland of skulls, standing over the white corpse of her consort, Shiva. Close to the Kali Temple is Mother Teresa's Home for the Dying. Although visitors aren't allowed in, you can apply to do volunteer work for short or long periods. Contact the Missionaries of Charity at Mother House on Lower Circular Road for details.
Not everything in Calcutta is old and decaying. Check out Tantra, the city's hippest nightclub, centrally located in Park Hotel, on Park Street. It's not quite London or New York, but the tequila shots and margaritas are highly recommended. The bouncing strobes and loud music give the place an air of anonymity, making it a cruising spot for the city's gay and lesbian population. There's a cover charge of about HK$40 per couple on weeknights, and HK$70 at weekends (tel:  33 2249 7336).
7 College Street
This is where India's second- oldest university, the University of Calcutta, was established in 1857. It's an interesting area to spend an afternoon, and not to be missed by serious booklovers, crowded as it is with overflowing shops and stalls selling new and used books at bargain prices. Titles cover myriad interests from art to celebrity biographies, Indian astrology, the Kamasutra, Ayurvedic medicine, and, of course, lots of texts for courses taught at the university and at Asia's oldest medical college, the Calcutta Medical College (founded in 1835) a stone's throw away. Stop in at the Coffee House, a legendary, damp, noisy, smoke-filled room, where the city's intellectuals once gathered to discuss life, art and the politics of rebellion. The coffee's not what it used to be, although for the sake of nostalgia try a cup of the watered-down brew. If you have time, hop on one of the few trams left in the city, which run through the area.
Take a walk down the Esplanade, the heart of Calcutta's commercial area, during rush hour for a glimpse of every type of transportation the city's 13 million inhabitants depend on - bicycles, careening minibuses and taxis, trams and the occasional auto-rickshaw. Traffic can be stuck in jams lasting 40 minutes - another reason walking is a sensible option. Along one side is the Calcutta Maidan (one of the last remaining expanses of green in the city), and you'll pass the crumbling facades of once impressive architecture such as the Metropolitan Building (now classified as a heritage building and in the process of restoration) and the century-old Firpo's Bazaar (or what's left - it was almost destroyed by fire in 2002). This is also a good place to shop for cheap but quality leather bags and terracotta jewellery (be prepared to haggle). As you walk towards Park Street, you'll pass the National Museum and the Fine Arts College.
9 The National Library
Visitors to Calcutta usually overlook the National Library on Belvedere Road, partly because it's frequently shut for months on end by labour disputes. If you're fortunate enough to find it open, it's definitely worth a visit. The library was founded in 1903, and built in the Italian Renaissance style. It used to be the residence of the Lieutenant-Governor of Bengal. Today, it's one of the city's 800-odd heritage buildings, and is India's largest library, with a collection of more than a million titles. It's open from 8am to 8pm, and a section of the books and periodicals - including the newspaper archives - can be accessed with a free day pass (tel:  33 2479 1381, www.nlindia.org).
10 New Market
Although air-conditioned shopping malls with escalators are cropping up all over the city, New Market (originally called Sir Stuart Hogg Market) is where Calcutta's smart set first learnt to shop. It's neither air-conditioned, nor organised, so be prepared for the heat and to spend time getting your bearings. And watch out for touts and phoney guides who'll offer to show you around. The main market is housed in a single-storey building with a red-brick Gothic clock tower, built in 1874. Shops selling similar merchandise are generally clustered together, and the market is still a good place to buy colourful Indian clothing, leather goods, dried fruit, and stone, bead and silver jewellery. Stop by Nahoum & Sons (Calcutta's only Jewish bakery) for excellent cookies, pies and fudge, as well as the dairy product shops further down this aisle that sell salty Bandel and creamy Kalimpong cheese, along with sweet and sticky dried mango slices known as amshaat.