Havana Old Town contains colonial buildings from the 16th century onwards

I sit on a bench in a tiny park, and the colour, music and exuberance of old Havana engulf me. The air is smothering - a hot, wet blanket, heavy with humidity - but heat cannot dim the joie de vivre of the Habaneros. An intoxicating blend of Spanish guitars and African drumbeats drifts from a nearby bar, where an elderly couple is performing an afternoon salsa. Workmen repairing a stone fountain add strange syncopated rhythms with their chisels.

Music aside, the streetlife is extraordinary. In the shade of a tree, an old man chats to his caged birds, a smouldering cigar dangling from his lips. Three barefoot boys in tattered shorts kick a dented can over the cobbles, splashing through puddles from last night's rain. A street-sweeper hobbles by, licking her ice cream. Another old crone squats in front of a sky-blue door, selling single cigarettes. Bare-chested men exchange jokes as they push barrows of rubble. A grizzled, toothless man approaches me and holds out his hand. I give him a few tiny coins.

As I look up, a woman leans from an ornate, rusty balcony to hang out washing and waves down at me. Beneath her, the peeling stucco façade of the once-grand house is criss-crossed with wooden scaffolding. It's a typical sight. The old town contains incredible architecture, with colonial buildings from the 16th century onwards. Many are crumbling and decrepit, but others stand newly rescued and restored, partly as a result of Unesco World Heritage funds. Open portals lead to vibrant art galleries and leafy courtyards.

On a corner, the house where Simón Bolívar once lived now contains exhibits illustrating his life - amusing ceramic vignettes depict him being born, being breast-fed, and later having sex in a hammock, as well as liberating Latin America from colonial hegemony.

Bolívar died aged 47, disillusioned at his failure to form a unified Latin American republic, but today "El Libertador" is revered as a saint. Passing his statue, I cross the street to a small café where, over a delicious guava milkshake, I ponder our own lack of equivalent heroes. Britons have nobody like Bolívar to look up to. Cubans are lucky, with several giants to worship - not lightweight media celebrities, but principled, visionary reformers.

'Living legend': Fidel Castro

Like him or loath him, Fidel Castro is one of them. There are few photographs of him, and no statues, but for most Cubans, Castro is a living legend who has maintained his communist ideals despite the collapse of communism elsewhere, and despite sanctions and embargoes from the "Enemy" to the north.

The Cubans I speak to all share Castro's patriotism and his distrust of democracy, and are intensely proud of Cuba's egalitarianism, education, health care and sporting achievements. None of them mention human rights or freedom of expression.

I wander on through a series of beautiful 16th-century squares, cordoned from traffic with huge cannonballs. In the exquisite Plaza Vieja, a group of tiny children appears with two teachers. The youngsters start their PE lesson - the boys in a circle, doing press-ups and star-jumps, the girls running in and out of the bollards. At a flower stall, a yellow motor-scooter taxi judders to a halt and an elderly passenger clambers from under the coconut-shaped canopy to buy gladioli and fragrant white mariposa - "butterfly" flowers.

Habaneros play music, laugh and dance at every opportunity, but times are hard. Beyond Plaza Vieja, the streets are potholed and strewn with rubbish, and families sit on doorsteps in front of squalid, sparsely furnished rooms. The average wage is £7 a month - food is scarce, and housing is in crisis. The Cubans I speak to hope that tourism and foreign investment will help to alleviate poverty, but admit that the tourist peso, worth 20 times the local peso, is itself creating class divisions between those with access to it and those without.

But despite this, Cubans remain cheerfully egalitarian, and as enthralled as ever by their most famous hero. I remember my own Che Guevara poster, pinned to my bedroom wall 35 years ago. Sixth-form pupils at the school where I teach have an identical poster in their common-room today - but nothing prepares me for his iconic importance in Cuba.

	One of Havana's ubiquitous vintage cars outside the Gran Teatro

Che was an Argentinian doctor, who spent only six years here, but his face and slogans appear on hundreds of Havana billboards. His huge portrait covers the side of a building in Revolution Square, and his photograph hangs in every classroom, where children pledge each day to emulate him - "Seremos como El Che". Gradually, I realise, I am falling into a sort of revolutionary pilgrimage.

I stop for a mojito in a café where 10 exuberant musicians are performing on guitar, six-stringed tres, double bass, flute, bongos, maracas, and clavés - two sticks banged together. The musicians are all men - machismo rules here - but their skins are of every shade from black to white, and they are all smiling. Their music is fantastic - long sets with false endings, rap sections, solo instrumental interludes - and the fun is infectious.