I call them “National Geographic Moments.” They are those times when we are off the grid or in a very unusual place, as if we’ve slipped though a wormhole and into the pages of a magazine.

Visiting the Dharavi slum in Mumbai was one of those moments.

We went on a tour of Dharavi in a group of four operated by the very professional Reality Tours. Over half of Mumbai’s 19 million residents live in the slums, an astonishing statistic, and there is no way to appreciate this dynamic city without visiting one.

There are over 10,000 diverse businesses operating in Dharavi, and we started our tour by visiting the recycling centers for which the slum is famous. Nothing goes to waste in the slum. We visited make-shift factories as men working in appalling conditions recycled plastic, aluminum, vegetable oil containers, and computer parts. Men burned off the excess oil and paint in cans and cleaned them so they can be resold to the manufactures. We saw people performing all sorts of tasks, from the menial (sorting plastic bottle by color) to the dangerous (shredding plastic in giant choppers). No one wore safety goggles or gloves, toxic fumes filled poorly ventilated rooms.

In addition to the recyclers, we saw small factories for sewing clothes, leather workers, small shops and supermarkets. We visited an area of Gujarati clay pot makers whose huge kilns sent caustic plumes of smoke into the sky, burning my eyes and choking me as we walked past. These artisans were some of the first inhabitants in the slum, back when it was on the outskirts and before the modern city swallowed it whole. It is clear that right in the middle of the city is not the best place to be burning fires to make clay pots, much less toxic fires of plastic and paint.

After touring the industrial area, we passed through the residential Muslim district. In the narrow alleyways men scooped out water from 50 gallon drums and bathed in the street. Open sewers bisected the tiny walkways. Trash was everywhere. It wasn’t any filthier than Delhi, India’s capital city, but it was still appallingly filthy.

We walked through an area of streets that were not in fact streets at all, but labyrinthian corridors barely 18-inches wide – a claustrophobe’s nightmare. We emerged from the corridors into the bright light of a small open area, a “plaza,” if you will. The open space was filled with illegally dumped garbage. On one side was a block of bathrooms and showers. Even though most of the huts now have running water and electricity, almost none have toilets. Each toilet at the community bathhouse is used by over 1000 people per day. In the morning long lines form, so many people just defecate in the street or in hidden spots, said our guide. At that time, as if to add effect to his statement, a small girl squatted down in a trash pile near us.

Our guides were Hindus and there was some evident bias in them towards the Muslims. The slums of Mumbai have been segregated by religion for 20 years now, ever since the Muslim/Hindu riots of 1992/1993. As we entered the Hindu side of the slum they pointed out how much cleaner it was. Indeed, it featured the cleanest streets I’d seen in India, regardless of religion or class. Women dried papad in front of their houses, kids ran along in private school uniforms, laughing.

All along the tour we had glimpses into the tiny homes of the slum dwellers. The average Dharavi resident lives in a 10ft by 10ft, one-room house. Each house has roughly 4.5 residents. Each tiny room serves as both kitchen, living room, and then at night when the residents unfurl mats and sleep on the floor – a game of Tetris to make them all fit – it becomes a bedroom. All the houses we looked into were clean, bright and orderly.

The residents of the slum are by now accustomed to the tour groups and no one asked us for money or hassled us. We, in turn, were not allowed to take photos and asked not to hold our noses or make faces when we encountered bad smells. I tried my best but I nearly gagged when we were in an area with goat and lambskins reeking in the hot air. Sometimes I caught a nostril assaulting whiff from the open sewer and I am sure my face betrayed me, that I showed disgust. Other times the spicy scent of frying garlic or curry would waft from an open door and I would salivate, no doubt showing an expression of pure joy.

There are plans to move the slum, relocate it’s residents and develop the prime real estate on which it sits, but any plan to relocate over one-million people will be met with fierce resistance. One thing that I have learned from visiting slums in Africa and now India, is that slums are vibrant, dynamic places. Life is hard, a struggle, but life can be happy there also. There are some rich people in slums, some middle class and educated people in the slums. They could move, but stay because in the end, it is their community, it is where they have friends and family. It is their home.

A day after the tour, I spotted a National Geographic from 2007 at a second hand bookstore. “DHARAVI: India’s Shadow City” read the headline. I bought it for 30 rupees, reading recycled words – apropos I thought. The photos in the article were of the places we’d seen. The cover photo was of the clay makers; there were photos of tiny homes, recyclers, ramshackle edifices and the slum dwellers like the ones we’d seen. It was a treat to get to visit a place off the grid like an Indian slum, a place I usually travel to only through the pages of magazines.

What are some off-the-gird travel experiences you’ve had?

I’d love to hear about them in the comments section.