It has been a trait of mine since I was young that whenever I'm at large in a British city I go around mourning what is not there, oblivious to the good things that surround me. A few days ago, in bright spring sunshine, I was walking past St Paul's Cathedral, but my thoughts were not filled with Wren's soaring architecture, the happy crowds of tourists or the glorious river sparkling nearby. Instead, I was annoyed at the plethora of chain restaurants that snaked around the side of the building. I found myself yearning for the cheery, idiosyncratic, family-run places that used to be there in years gone by. In fact I have no idea whether that is true, but I was assuming St Paul's used to be surrounded by such places. It might have been ringed with shops selling fur coats and Nazi regalia, for all I know.
Until recently I suffered this gloomy outlook most severely with my home city of Liverpool; my melancholy feelings towards modern city scapes spring from the experiences of my youth. When I was a kid, I lived in a wonderful city of grand commercial buildings side by side with narrow streets full of bustling energy. There were packed cinemas, basement clubs in which the music of bands who would go on to change the world spilled out on to the pavement, and splendid theatres that showcased the finest modern writing in Britain. There was a sublime Victorian elevated railway with wooden carriages, from which you could look down the funnels of the giant ships that crammed the docks.
Then suddenly it was all gone - the docks were empty, the cinemas closed, the clubs closed, and most of the town centre and the overhead railway was demolished. From the terraced house where I grew up to the river two miles away, there was suddenly nothing but rubble. I recall wandering the ruins like some 12-year-old Cassandra, destined to be heard but never believed, saying to people in my prepubescent voice: "Can't you see they're destroying whole communities with this terrible experiment in urban planning? It's a disaster, a complete disaster!"
When the BBC asked me to spend nearly four months there last year making Alexei Sayle's Liverpool, I thought that my tale would be one of loss and woe. Strangely, the longer I spent in 2008's European Capital of Culture, the more I came to see that there was a huge amount that had survived the destruction of the 1960s and 1970s and a large number of new buildings concerned with culture and the arts being created.
For example, familiarity had made the extraordinary group of buildings that greets you as you leave Lime Street Station invisible to me. It was only through filming on St George's Plateau and researching their history that I came to see them afresh. In the early 19th century, Liverpool was a city without refinement, a place where the ruthless pursuit of wealth was everything, and it was only through the efforts of a group of progressive businessmen - particularly William Roscoe, well known as an anti-slavery campaigner, who dreamed of making Liverpool into a European cultural centre to rival Renaissance Florence - that the city came to have this remarkable collection of buildings.
Among other achievements, Roscoe inaugurated the Botanic Gardens, and his art collection was the foundation of the Walker Art Gallery, the first public gallery in Britain, which is to your right as you leave the station, and a place where I spent hundreds of teenage hours. At the moment it has a tremendous exhibition on "Art in the Age of Steam", with works by Manet, Frith, Monet, Van Gogh and Hopper. It is appropriate that this should be the only European showing for this exhibition, because among its many firsts Liverpool had the world's first passenger railway. The first train left from Edge Hill, the world's oldest operational station, in 1830.
The Walker is part of a group of structures that includes at its centre St George's Hall, hailed by Pevs ner as "one of the finest neo-Grecian buildings in the world". St George's is directly opposite Lime Street railway station. It contains law courts and concert halls. A competition to design the hall in commemoration of Queen Victoria's coronation was won in 1839 by Harvey Lonsdale Elmes, a 25-year-old Londoner. The idea was to have the grandest (which meant largest) public building in the country, and the architect's plans were superimposed on those of Birmingham Town Hall and many other civic buildings just to make sure that it outsized them all.
Probably the group of buildings that is most associated with Liverpool is "The Three Graces" at the Pier Head - namely the Liver Building, the Cunard Building and the Port of Liverpool Building, which together symbolise Liverpool's great achievements in dock construction, shipping and insurance. After spending a lot of time filming them, I began to get the feeling that the city fathers, having done big, wanted to move on to trippy. To me, there is a hallucinatory quality about these three buildings, particularly to the Liver Building, which is aided by the two giant mutant chicken birds tied to the northern and southern towers.
The Albert Dock is the UK's largest group of listed buildings, and is named after Prince Albert, who opened the complex in 1846. It was designed by the engineer Jesse Hartley and covers a surface area of nearly four and a half acres. Today it houses the Tate Liverpool art gallery, opened 20 years ago in perhaps the first attempt in Britain to jump-start the economy of a city by building a gallery. Recently, as part of the birthday celebrations, I took a confused group around the current exhibition "The 20th Century: How It Looked and How It Felt", but you'd probably enjoy it more without me giving you my insane opinions on Stanley Spencer or Mona Hatoum. In recent years, the Tate has been joined by a maritime museum and the International Slavery Museum; this last opened in August 2007.
Apart from its wonderful buildings (the city has more listed Georgian properties than Bath), Liverpool has the best parks outside of London. The oldest is Sefton Park, which is one of the largest in England. Begun in 1867, the park includes a cricket pitch, a lake, an iron bridge spanning a fairy glen and the main attraction, the Palm House, a Victorian glasshouse that opened in 1896. This contains plant species from Africa, Asia, America and Australia.
The Palm House found itself caught up in the ideological schisms that tore through Liverpool in the 1980s. The Trotskyist city council let it fall into disrepair and instead built its own park, Everton Park, probably the most recently founded public park in England. Eschewing anything so bourgeois as flower beds, bandstands or shelters, it is nevertheless a striking place composed of nothing but trees and grass. Although I would not linger there at night, it is an amazing place and there is a lookout where you get a wonderful view of the centre of Liverpool and its surroundings, across the Mersey and into North Wales.
Among its many claims to fame, Liverpool has the most theatres outside London, and even in the bleakest days its duo of pointy-bearded playwrights - Willy Russell and Alan Bleasdale - shone a light into the darkness. Many of their early works were premiered at the Everyman Theatre in Hope Street, and that pioneering work continues. In 2006 the Everyman put on the docudrama-style Unprotected, personal accounts by the mothers of murdered street sex workers in Liverpool, and now Ten Tiny Toes, a similar piece about soldiers killed in action.
So much has been destroyed and there are still huge pockets of deprivation in Liverpool. According to one community representative I spoke to, my old neighbourhood is now the poorest district in Europe. If art can be a force for positive change, then the city has a good chance of hauling itself out of poverty. Or, at worst, as they go under, the people of Liverpool will be able to enjoy lots of plays, concerts and art installations.
"Alexei Sayle's Liverpool" begins on BBC2 on Friday 6 June (9pm)