Walking down 13th Street in Philly (no one calls it Philadelphia here), who do I spot on the corner of Pine Street? Ol' Blue Eyes chewing the fat with rock icon Frank Zappa and the ever-debonair Frankenstein. Sinatra and his pals are accompanied by some other well-known Franks, including Franklin D Roosevelt and Aretha Franklin. All have been immortalised in a mural on the exterior wall of Dirty Frank's. The name says it all – this is a bawdy, down and dirty drinking den, in the heart of the city.
Famous Franks is one of more than 3,000 murals created by the Philadelphia Mural Arts Program. The scheme was conceived in 1984 by the then-Mayor of Philadelphia, Wilson Goode, to combat inner-city graffiti and gang culture. A young muralist called Jane Golden was brought in to reach out to graffiti writers and redirect their energies into constructive mural painting. And reach out she did, with the result that this small community-based initiative snowballed into the largest public arts programme in the US.
I join a walking tour led by Mural Art's energetic young tour manager Ryan Derfler. We wind our way through the narrow, tree-lined streets of Center City. This comprises the bustling downtown and historic sections of Philadelphia, and is the district that boasts the highest concentration of murals.
The tour takes us past some of the city's top attractions, including Independence Hall (now a World Heritage Site), where the Declaration of Independence was first adopted. A block away is the city's most-visited attraction: the Liberty Bell Pavilion, where the cracked bell (made in east London) reduces grown American alpha males to tears, such is its cultural resonance.
Our tour takes in a good variety of murals, some flamboyant, some reflective and some – such as Gimme Shelter and In the Shadow of the Wood, loosely based on Finnegans Wake – with a wry, subtle humour.
Because the programme is community based, the murals tend to reflect the ethnicity of individual neighbourhoods. In Chinatown, they have Asian themes: titles include Our Vision of Chinatown and Asian Muses.
We end our tour close to the Reading Terminal Market, a vast indoor hub for the budget gourmet, and slip inside for soft pretzels. (Another Philly-food institution; head for the Amish section for the best ones.)
In Philadelphia, you are never short of an opportunity to sample any number of local specialities – and Center City is awash with goodies. The artery-clotting Hoagie (a submarine-style sandwich) and the Philly Steak (a cheese and steak sandwich) are available on almost every block: Shanks on 15th and Chestnut hits the spot for me.
Some of the mural tours on offer from Mural Arts include food stops. The keen foodie with an MP3 player should consider taking the self-guided walking tour, which you can download from the Mural Arts Program website.
Later I tour several outlying neighbourhoods, and it is here that the social impact of the murals is most poignant. Tensions run high in some of these disadvantaged neighbourhoods, which are well off the tourist trail. They are best visited on the group tour, unless you are built like a prop forward – think The Wire and you've got the picture.
A frenetic Jane Golden has said that "Community public art can knit people together in a way that other things can't." Nowhere is this more evident than at The Peace Wall, a mural created by Jane and another muralist, Peter Pagast. Jane conceived the uplifting mural – with its theme of unity – following a violent incident in a racially divided neighbourhood.
Even after 25 years at the helm, Jane is still the heart and soul of the programme. She strikes me as a high-octane whirlwind with the energy of Wayne Rooney, constantly initiating and evolving. One of her current projects sees muralists going into the State prison, and helping inmates paint murals on to parachute cloth (a technique developed by the Mural Arts Program), which are then hung on the streets of Philadelphia.
Healing Walls, in North Philadelphia is a fine example of the fusion of art, social conscious and redemptive values. Other murals, such as the exquisite Holding Grandma's Quilt, chronicle the history of a community – in this case, the quilt-making skills handed down amongst African-American women.
I am particularly captivated by the extravagant murals in the Hispanic neighbourhoods of North Philly. A personal favourite is the pair of murals Crossing the Puddle that straddle North 5th Street. They perfectly capture the agrarian and musical traditions of the Hispanic migrants' homeland.
Wherever you go in Philly, whether by foot, car or train, you stumble into another, often arresting work. Some murals occupy no more than a small wall, storefront or side of a house, while others adorn complete sides of multi-story industrial buildings.
The mural credited with putting Philadelphia on the national stage is Meg Saligman's landmark Common Threads. The flamboyant mural – a tribute to Philadelphia's youth – adorns the whole side of an eight-storey building at North Broad Street and Spring Garden Street. At the other end of Spring Garden Street, on North Delaware Avenue, is another of Saligman's large-scale murals. Tribute to the Flag, painted in the aftermath of 9/11 as a tribute to the victims of the tragedy, is a highly emotive work. It left me breathless the first time I saw it, just after it had been painted in 2002. A huge American flag appears to be draped over the side of a large industrial building. The mural covers 2,281 square feet; each square foot represents one victim of 9/11. The red in the flag has subtly been changed to match a blood-red. It's a superb example of modern art with a real emotional resonance that captures the turbulent mood of America in the wake of the attacks.
Saligman aficionados are eagerly awaiting one of her most ambitious projects – a large-scale work, which should be completed by the summer. It will feature LED lights and a special paint that changes colour in different light. If only Michelangelo had thought of that, we'd have a very different Sistine Chapel.
Picture perfect: Shooting murals
* Stand as far away as you can from the mural and position the camera as horizontally as possible. It is when you tilt the camera up to get the top of a building in the frame that you get those annoying converging verticals.
*Raise the camera position by standing on a wall.
* It is more effective to shoot in portrait format and crop out the unwanted foreground later.
* See coplans.co.uk for more photographs of Philadelphia's murals.
Travel essentials: Philadelphia
* Philadelphia is served from Heathrow by BA (0844 493 0787; ba.com) and US Airways (0845 600 3300; usairways.com).
* America As You Like It (020-8742 8299; americaasyoulikeit.com) offers a four-night package to Philadelphia, staying at the Loews Hotel, from £575 per person, including BA flights.
* Most tours operate between April and October but Mural Arts (001 215 685 0750; muralarts.org) tries to make sure that some out-of-season murals tours are available. Private tours are on offer year-round. Walking and bike tours start at $10 (£6.70) per person and trolley tours at $25 (£16.70).
* "Philadelphia Murals and the Stories They Tell" by Jane Golden and others is available from amazon. co.uk, price £19.94.
* Philadelphia Tourism: 0844 880 6853; philadelphiausa.travelReuse content