The way to heaven is too steep, too narrow, for men to dance in and keep revel rout. No way is large or smooth enough for capering rousters, for jumping, skipping, dancing dames but that broad, beaten, pleasant road that leads to HELL.

WILLIAM PRYNNE, Histriomastix

To be a teenager in 1970 was to suffer an excess of gravity. I watched them move slowly along Camden High Street, boys and girls alike with faces half-closed behind long centre-parted hair. The shape their clothes made was that of something being pulled down into the earth: scoop-necked tops, peardrop collars, flared or leg-of-mutton sleeves, and flared ankle-length skirts and trousers made of cumbersome corduroy, denim or hessian. They wore bare feet or sandals in summer and otherwise heavy boots or wedge-platform shoes. In winter they wrapped up in afghans, antique fur coats and greatcoats, hats and scarves. Their colours were vegetal – umber, ochre, aubergine, mushroom, sage. They looked damp.

I thought that their music must be the key to becoming like them. I got to know it as we absorb music in passing but can remember only its seriousness and weight. The record sleeves had the same droopy, glutinous lettering as the clothes-shop signs. The music of lumbering lost creatures. Is that what I had to become?

There was a higher realm, occupied by beautiful men who might be women, who wore feather boas and silver eyeshadow, their hair in ringlets, solid wedges and angular curtains, and who seemed remote, gentle and dangerous. If the Camden hippy colours were earthbound, the glam rock colours were like the whirl of gas around a planet. I glimpsed these figures passing in and out of adult doorways, their paths through the city crossing mine as indifferently as if we were in separate orbits. So much about them was concentrated in their surfaces that they seemed weightless. They suggested a perfection which I would have to move through many worlds in order to attain.

They looked like David Bowie on the cover of Ziggy Stardust. He poses on a narrow pavement strewn with rubbish in a city of gas lamps and cardboard boxes. It is dark and raining. The buildings are soggy brown, the sky grey, the huddle of parked cars black, grey and white. Bowie has silver-green-blond hair, silver-green skin, and is wearing a jumpsuit that looks like a spacesuit.

Such creatures were neither bad nor good – they were other. They complicated my idea of beauty and persuaded me to submit to much that I didn’t understand. Their songs might as well have been written in another language, but they were delivered with such conviction and style that they too were a triumph of surface.

There was a great deal of music-making, and a feeling that anyone could and should do it. A lot of people carried guitars and would sit down and play wherever they were – on a patch of grass, at a bus stop, at any kind of gathering. A group of local musicians had set up a Saturday-morning music school for children, and I played the violin in the orchestra and sang in the choir. That year, the Young Music Makers staged a production of The Pilgrim’s Progress at the nearby Roundhouse, a vast circular building I knew well, but only from the outside. I had never imagined a way into it.

The Roundhouse was one of my childhood’s architectural features, like the Mermaid Theatre or the Post Office Tower. I took such names literally and had the notion that in the darkness of the theatre our legs turned into fishtails, that letters were sorted twenty floors up and that the Roundhouse was someone’s house, only round. Then I was told that it was a place where the Victorians had repaired steam engines and I wondered how they got the train in – perhaps coiled like a snake. This information convinced me that the Roundhouse must be even bigger than it looked. Even so, steam engines had apparently become too large for it and, for the next hundred years, the Roundhouse had been used to store thousands of bottles of whisky and gin. So the train uncoiled itself, the steam evaporated and that vast space filled up with row upon row of glistening bottles. Not in boxes of course, but lined up as they would be behind the bar in a Western, reflected in mirrors, only in the Roundhouse there would be no mirrors but more and more actual bottles wherever you looked. I wondered how anyone could walk among them without knocking one and what would happen if one fell. Would it be like dominoes, bottle after bottle crashing down till Camden was awash with alcohol and glass?

The trains and the gin were long gone and by 1970, the Roundhouse had become a rock venue. I saw the posters: David Bowie, Marc Bolan, Jimi Hendrix, Pink Floyd, The Rolling Stones, The Doors and The Who, names which were for me part of the musical ether through which teenagers moved. This featureless, squat building was now a fairytale castle.

Now I was to enter the castle. Of course it was not as large as I had known it to be and the bare brick walls said nothing of trains or gin or Jimi Hendrix. I listened to someone explain that here in the centre there had been a vast turning circle on which to move the engines, and my train uncoupled and diminished to a squat front end. In order to change into our black-and-white pilgrim attire we were taken down into the undercroft, the rings of tunnels and corridors beneath the turning-circle floor. I was so transfixed by the undercroft that I remember nothing of the performance. I was not touched by the music, or by the story of the pilgrim, and I had found no trace of the building’s other musical life, no clue, no key. I recently asked my brother. ‘All I remember,’ he said, ‘is running around in those tunnels.’

Would I really one day be released on to the broad, beaten and pleasant road of Camden High Street? Would I learn to move slowly or would it just occur, this arrival of gravity? I could neither ask these questions nor answer them. All I could do was keep running round and round in my eight-year-old orbit until the turning circle moved like some cosmic pivot and I was tipped into another orbit and a heavier atmosphere.