However, the destinations, which can be linked by hired Ambassador - rolling like a mother ship amid the troughs and crests of tarmac - into a large figure of eight, are worth a dozen brimming sick-bags.
Indore is now labelled the Baby of Bombay, and already spews forth enough pollution to make any parent proud (currently seventh in the nation's smog parade) but it makes a practical starting point being just an hour from both Delhi and Bombay by plane. Its own palace does not, however, live up to the gates which are exact replicas of those outside Buckingham Palace, and an outsize Queen Victoria sneers at its fussy facade from her plinth in the overgrown garden.
Far more splendid is the marble main building of The Daly College Public School, founded a century ago for the education of the local prince and about a dozen others who arrived by elephant with the servants from their far-flung estates. Nowadays, 1,600 students do battle for grades, pausing only to play hockey and cricket against archrivals Mayo College, an even princelier institution an overnight train ride away, up the line in Rajasthan.
An Ambassador and driver - a combination which can still be had for less than 1,000 rupees a day (about pounds 15) - should take you west towards Mandu, the walled city, pleasure resort and royal capital, via an astonishing Art Deco palace, the Jhira Bagh, which is now a luxury hotel.
A royal row meant that its huge Bauhaus halls and suites, uplit by GEC, were unused from the moment the old palace was modernised in 1943. Then, three years ago, the new owners threw open the doors, scrubbed the Italian marble floors and repainted the walls to turn it into one of India's most fascinating independent hotels.
The 15th-century ruler of Mandu, Ghiyath Shah, confirmed its reputation as the City of Joy by installing his 15,000-strong harem in what he called the Ship Palace, "crewed" by a further 1,000 Turkish female bodyguards. Also in the Royal Enclave lies the beautiful Hindola Mahal, or Swing Palace, with its sloping walk, and the Champa Baodi, an underground well, once perfumed with champak flowers, which has specially ventilated cool- rooms for surviving the summer. Evidence of heat-beating strategies - serpentine water channels and wind funnels, for example - abound in Mandu, though the method most favoured by today's "citizens of joy" is leaping in and out of the great, green water tanks.
But Mandu's highlight is Roopmati's Pavilion, built by Baz Bahadur for his Hindu mistress who insisted on overlooking the sacred River Narmada. The magnificent views from this perch, 300 metres above the vast plain, run into South India, said to begin at the far bank of the river, which flows East to West from your next destination, Maheshwar.
The temples and fort complex of this ancient city were revitalised by the 18th- century Holkar queen, Rani, whose descendants still occupy the palace, manage production of the area's famous striped saris and swim with commoners from the ghats (stairs leading to the river) every day.
After another two-hour, axle-flexing drive up the Narmada, your Ambassador lets you out at Omkareshwar, an isolated village built on a sacred island shaped like the Hindu symbol Om. The motorised launches destroy all peace as they negotiate the strong current but do give fine views of riverbed- combers filtering the holy waters for rupees, and tense Western campers trying for enlightenment while simultaneously defending their backpacks from roaming bands of monkeys.
The Sri Omkareshwar Mahadeo temple contains one of India's 12 naturally- formed jyotirlingas, thrust up from the rocky hillside and believed to be a representation of Siva. The surrounding lanes, which have been periodically ransacked by Muslim aggressors, now heave with pilgrims clutching their souvenir stone phalluses, and the intensely devotional atmosphere is reminiscent of Varanasi, India's holiest city in adjoining Uttar Pradesh.
Hubbing back into Indore, head north to Shivpuri which offers one of the state's several National Parks (mainly deer and tigers captive behind tennis-court wire) nicely viewed from the verandah of George Castle, a solid folly put up for the Emperor, King George V in 1911, but never graced by him. More elegant are the Hindo-Islamic style chhattris, marble burial chambers of the Gwalior family supported by columns inlaid with lapis lazuli and onyx, lit through blue glass windows and pervaded with a sense of well-tended peace.
The onward road is better because you are occasionally enjoying Uttar Pradesh's more generous maintenance budget but the bonnet of the Ambassador will be rising and falling in grand style by the time you reach Orchha, a palace complex bristling with vultures and, nowadays, a few tourists. Both are easily accommodated, meeting only on the upper corridors and the hanging balconies of the beautiful Jahangir Mahal, still flecked with the remains of cobalt and turquoise tiles which must have made the palace gleam for the Muslim Emperor Jahangir when he visited his Bundela allies in the 17th century.
Best viewed from the medieval bridge across the Betwa are the 14 royal sandstone cenotaphs, massive square tributes tapering to jagged points further ornamented by vultures' profiles. They look down on the newly opened Orchha Retreat luxury hotel, which trespasses insensitively on this superb site.
And now to Khajuraho, which can quicken the modern pulse just as it did the Victorian when eager British soldiers galloped in over even rougher terrain and "discovered" the frozen ecstasies of these inventive and all-embracing lovers. For a thousand years their most satisfied sandstone smiles have kept sex in the air here, but so much else is represented - warring, worshipping and dancing - in relief so high as to be almost three-dimensional. Astonishing elephant friezes run for yards, trunks as unblemished as the dozens of perfect breasts: the Muslim sackers, who did so much damage at Omkareshwar, did not reach distant Khajuraho. The Chandela dynasty, it is sometimes suggested, were entertaining the gods with their carvings in order to divert wrath - a ploy which seems to have worked.
Tacking back westwards, you reach Sanchi, a 3rd-century BC Buddhist hilltop site whose carving astonishes even recent veterans of Khajuraho. The Great Stupa is shielded by four toranas, or gateways, above which perfectly rendered elephants vie with tiny intricate human faces and floral motifs. And from the Eastern gateway hangs a sandstone nymph, her hip thrust out in what has since become a key classical dance pose. Perhaps she will stand for you as a final memento of one of India's slowest, bumpiest, most fascinating road-trips.
Flights to Bombay from Trailfinders (tel: 0171-938 3366) include Delta Air via Frankfurt, pounds 370 between 1 October and 5 December, and Gulf Air between now and 10 December, pounds 425. Prices include taxes. For good internal flights (Bombay to Indore, for example) call Jet Airways (tel: 0181- 970 1525 for UK reservations).
The best way to get around most parts of India is to hire an Ambassador and driver. The car (without air conditioning) costs 700 rupees per day (about pounds 13).
The author's bookings were made through Frequent Travels, Indore. Contact Mr and Mrs J Walia, Frequent Travels, 103 Apollo Arcade, 1/2 Old Palasia, Indore 452 001, Madhya Pradesh (tel: 0091 731 554753).
WHERE TO STAY
Hotel recommendations include:
In Shivpuri: Tourist Village run by Madhya Pradesh Tourism (tel: 0091 7492 2600): cottages in a compound.
In Orchha: Sheesh Mahal (no telephone): rooms inside the Royal Fort. Alternatively, there is the plush Orchha Retreat Hotel on the riverbank (no telephone).
In Khajuraho: Holiday Inn (tel: 0091 7686 2086): good pool.
In Sanchi: Travellers' Lodge run by Madhya Pradesh Tourism (tel:0091 7592 81223)