This teeming West Bengal metropolis on the banks of the Hooghly river is home to some five million people, and combined with urban sprawl, becomes one of the world's largest cities, at close to 16 million.
Arriving at Chandra Bose International in the early hours of the morning, my wife and I felt that nearly all of those people were there as the exit doors opened. If you haven't been to India before, and we had, the sight of so many faces all clamouring for your attention along with the cacophony of noise can be a daunting experience - welcome to the wonderful, chaotic and exuberant country of India.
Looking out of our hotel window, we see that Kolkata never sleeps. People are on the streets at all hours - auto rickshaw carts loaded with goods, elegant sari-clad women pedalling ancient upright bicycles, businessmen being ferried around in hand-pulled rickshaws - the only place now that still allows it, as it provides income for desperately poor people and the city authorities cannot justify banning it.
Kolkata had the world's longest-serving democratically elected communist government from 1977 to 2011, but the new authorities now in power have started a city facelift, ordering official buildings, traffic lights, flyovers, even streetside tree trunks to be painted blue, the favoured colour of the chief minister of the State. Even the famous yellow Kolkata Ambassador taxis were to receive a new coat of paint, but locals felt that was going too far.
One of the most visited places in the city is known simply as Mother House. Down a narrow laneway that has few signposts lies the revered tomb of Mother Teresa, in a simple and humble building that this saint of the poor called her home, and from where her followers still carry on the charitable work in her name. Her tomb is viewed by thousands.
In the north-west part of the city close to the Howrah Bridge is the Malik Ghat flower market, the biggest fresh flower market in India, which is open every day for trading. Flowers are bought for weddings, events and festivals, and gods and goddesses have their own special flowers. The alleyways are narrow and crowded and walking through the market is a colourful and fragrant experience. Our guide, Bhargab Chatterjee, is a mine of information and an enthusiast for the city he loves.
Moving on to the northern fringe of the city, we come to Kumartuli, the traditional home of the potters, or idol makers. They have been working here for about 300 years, and have become world famous for their detailed clay figures of Hindu gods and goddesses.
The artisans can be seen in their workshops open to the street, and happily allow visitors inside to view them at work. They first make the basic figure with straw and bamboo, then put on three or four layers of clay, mould the detail while wet, then add colour and decorative items.
By road about 50km out of Kolkata is the hamlet of Aatpur, home to some beautiful terracotta temples, the finest being the Radhagobinda, built in 1786 and richly decorated with panels of gods and Krishna scenes, as well as depictions of early European lifestyles, showing the transition to colonialism. The surrounding area is dotted with old, crumbling Shiva temples.
Back in the city, in a neglected corner of St John's Church graveyard stands the monument to commemorate the victims of "the Black Hole of Calcutta". In 1756, 146 English colonists and Indian allies were crammed into a Fort William dungeon 4m by 5m by the then Nawab of Bengal. Only 23 survived the overnight ordeal. The original fort has long gone, but the memorial remains, a reminder of this region's turbulent past.
Memorials abound at the nearby Park Street cemetery, a haven of quiet in this noisy city. Paying a few rupees to the gatekeeper, you enter a place of huge and grand colonial mausoleums, most of which seem to be the resting place of English families who lived very short lives; the hardships of life in the 1700s saw most die in their 20s and early 30s, and there are poignant reminders of the sad, short lives of children, many living but a handful of years. This cemetery is now a heritage site.
Kolkata is a fascinating place to visit; crowded, noisy, and chaotic, but colourful, friendly and warm-hearted as well. It is India in a nutshell.