Delhi: the metropolis of seven cities

Old Delhi is where the city's Mughal layer is densest. Chandni Chowk, the avenue laid out in the mid-seventeenth century by Shah Jahan's daughter, remains one of Asia's most concentrated commercial streets — cycle rickshaws, wholesale markets, silver dealers, spice traders and food stalls operating in buildings whose structure has not fundamentally changed since. The Red Fort anchors its eastern end: Shah Jahan's sandstone-and-marble palace complex, with the public and private audience halls and the marble pavilions of the Rang Mahal along the eastern wall. Opposite, the Jama Masjid is the country's largest mosque, and the climb up its southern minaret gives the best view over the old city's rooftops. The lanes are the real subject, though. Paranthe Wali Gali has fried stuffed parathas since the 1870s; Khari Baoli is Asia's largest wholesale spice market and the turmeric aisle alone justifies the detour; Dariba Kalan handles silver and jewellery. Navigate by cycle rickshaw rather than on foot or by car — the drivers know the lanes, and nothing else fits through them.

If you see one monument in Delhi, this is the one. Humayun's Tomb, finished around 1570, is the prototype the Taj Mahal refined: red sandstone inlaid with white marble, set inside a formal Persian garden divided into quadrants by water channels, with a double dome and a rhythm of arches and alcoves that makes the family resemblance immediately obvious. The wider complex holds smaller tombs and mosques, and the restored Sunder Nursery gardens next door are among the best-kept green space in the city. A short walk south lies the Nizamuddin Dargah, shrine of the fourteenth-century Sufi saint Nizamuddin Auliya, where qawwali devotional singing fills the courtyard on Thursday evenings — crowded, intense and genuinely devotional rather than performed for visitors. The surrounding Nizamuddin Basti keeps its medieval character, with the tombs of the poet Amir Khusrau and others tucked into residential lanes that most visitors never enter.

The Qutub complex in the south holds the capital's oldest standing monuments, beginning with the Qutub Minar itself — a victory tower begun in 1193 and still the tallest brick minaret in the world, its five storeys shifting between red sandstone and marble as successive rulers added to it. The adjoining Quwwat-ul-Islam mosque, the first in India, was raised from the dismantled material of earlier temples, and the recycled carved pillars are visible throughout: an architectural palimpsest that mirrors the city itself. In the courtyard stands the Iron Pillar, a fourth-century column whose resistance to rust is still discussed by metallurgists. The real reward is next door: the Mehrauli Archaeological Park spreads over two hundred acres and more than a hundred monuments — Balban's tomb, the Jamali Kamali mosque, the stepped well of Rajon ki Baoli — mostly unmarked, mostly empty, and the single best place to feel eight hundred years of building, ruin and rebuilding sitting in one landscape.

The southern city hides its history in plain sight. Hauz Khas combines a thirteenth-century reservoir, madrasa ruins and a sultan's tomb with a contemporary neighbourhood of boutiques and restaurants in the urban village around them, which makes for an unusually pleasant late afternoon. Safdarjung's Tomb is a late-Mughal garden tomb that previews the Taj's symmetry at smaller scale and a fraction of the crowd. Agrasen ki Baoli, a stepwell hidden between office towers not far from the centre, drops away from street level in a hundred-odd steps into cool darkness — one of the city's most atmospheric spaces and free to enter. What these have in common is accessibility: all are on or near the metro, none needs advance planning, and none is crowded in the way the headline monuments are. They are the reason Delhi rewards a second and third visit rather than a single pass.

How Indian food works region by region — and where Delhi's chaat sits in the national grammar — is set out in the India food guide. What belongs to the city is a specific claim: this is where North Indian restaurant cuisine as the world knows it was codified, largely by Punjabi families who arrived after Partition and rebuilt their trade around the tandoor. Butter chicken and dal makhani were invented in Daryaganj in the 1950s, and the restaurant that did it still operates. Near the Jama Masjid, Karim's has served Mughlai food since 1913 and its slow-cooked nihari is the reference version; Al Jawahar across the road is its equal with shorter queues. In the old city, the parathas of Paranthe Wali Gali remain non-negotiable. South Delhi holds the modern end — Khan Market and Hauz Khas concentrate the restaurants reinventing Indian cooking with real technique. For street food: chole bhature in Paharganj from breakfast onward, chaat wherever the queue is local, and in December and January the winter-only milk-foam sweet daulat ki chaat, sold by a handful of old-city vendors and worth seeking out deliberately.

Delhi shops at several registers and they are worth distinguishing. Chandni Chowk and the lanes off it are wholesale and specialist: spices, silver, textiles, wedding goods, sold in quantities and at prices that assume you are in the trade. Dilli Haat is the opposite — a permanent, purpose-built craft bazaar where stalls rotate by state, so it functions as a survey of Indian handicraft under one roof, with a regional food court attached. Hauz Khas village mixes boutiques and design studios into the ruins at its centre, which makes for browsing rather than buying. Chor Bazaar and the Sunday book market at Daryaganj are the salvage end — worth a morning if the hunt is the point rather than the purchase. The capital district's own retail, from its Georgian shopping circus to the fixed-price state emporia, is a different register again and belongs to that guide.

The Delhi Metro is the best urban transit system in India — clean, air-conditioned, extensive and still expanding — and for a visitor it is the difference between a manageable city and an exhausting one. A stored-value card pays for itself immediately and works across the network, including the airport express line into the centre. Ride-hailing and auto-rickshaws fill the gaps for the first and last mile; prepaid stands at stations and monuments avoid the usual negotiation. The one habit that saves whole afternoons is refusing to cross the city by road during peak hours, roughly mid-morning and again from late afternoon into the evening; the metro is unaffected by the traffic that makes those hours miserable. Security checks at stations and monuments are routine and add a few minutes each time, so build a small buffer into a day with several stops. Intercity travel — trains to Agra and Jaipur, the wider rail network, domestic flights — is covered in the getting around India guide.

Delhi's climate runs to extremes and the calendar matters more here than in most Indian cities. Winter, from November to February, is the pleasant season for sightseeing — cool days, cold mornings, and fog that can delay flights and trains. Summer, from April into June, is genuinely severe, reaching the mid-forties with dust storms, and outdoor sightseeing in the middle of the day stops being sensible. The monsoon breaks the heat from July into September and brings its own humidity. The complicating factor is air quality: for several weeks each year, typically from late autumn into winter, a combination of regional crop burning, vehicle emissions and still winter air pushes pollution to levels that affect healthy visitors, not only vulnerable ones. Check a live air-quality reading when planning travel in that window, treat a well-fitted mask as ordinary equipment rather than an overreaction, and know that February, March and October are usually the clearest months for a city break here.

In the middle of all this sits an entirely different city: the imperial capital laid out from 1911, with its avenues, roundabouts and sandstone institutions, the ceremonial axis running from the war memorial arch to the presidential palace, and the diplomatic enclave that makes Delhi the country's consular centre. It is a separate administrative entity as well as a separate urban idea, and it is covered in its own right in the New Delhi guide — including the practical side for anyone whose trip involves an embassy or visa-centre appointment. For pure sightseeing the two read as one city and you will move between them without noticing; for planning, it helps to know that Old Delhi's monuments and New Delhi's institutions sit in different halves of the map and rarely combine well in a single day.