A real American drinking den should be dark, slightly seedy and full of local characters. Nowhere does the dive bar better than San Francisco

Long before San Francisco was overrun with hippies, then by dot-commers, then by failed dot-commers who became hippies, the city was a rough-and-tumble wild west town, more Deadwood than Deadhead. Now the city is teeming with health food stores, boutiques and obscure shops that sell lovely little things, and it's hard to spot these Gold Rush roots, but they do live on: in the Bay Area's many dive bars.

What is a dive bar? I'd say it's any place where gin and tonic is considered a "fancy drink", where "dank" is the interior design of choice, and where beer-battered lamprey drizzled with truffle oil is a thing of science fiction. It's why Homer loves Moe's, why Norm loves Cheers - a place of tall tales, of low expectations, a piece of undiluted, rarely seen Americana. As a former Bay Area resident and lover of dives, this is my ultimate tour of the best bars - long-term favourites as well as a couple of new recommendations.

I started at Clooney's in the Mission (1401 Valencia Street, 001 415 826 4988). Why? Because Clooney's opens at 6am. Legend has it that when the building next to Clooney's burnt down, the fire department were unable to remove the denizens from their stools. At the crack of dawn on a Tuesday morning, there was a little more energy on show. Five different televisions displayed five different programmes, each provoking a commentary from those either ending or beginning their drinking day. The scene in this neon-clad concrete box is not exactly convivial - more suspicious and badly lit - but as an easy-going neighbourhood bar it's an excellent place for a cheap beer and eavesdropping.

After Clooney's, a spot of breakfast was in order. The Silver Crest (340 Bayshore Boulevard, +415 826 0753) appears to have dropped into the Bayshore area from the kind of mid-western town that's invaded by unconvincing aliens in 1950s B-movies. It's a diner with eggs and potatoes in the front and a sliver of a bar in the back. The elderly Greek patron behind the bar will give you a shot of ouzo if it's your first time in the place, and there's a mighty collection of vintage pinball machines, and table jukeboxes that seem to feature just two tracks: one named "Greek" and one named "Happy Birthday".

In an attempt to work off my fabulous Silver Crest breakfast I visited a sports-themed bar in the Sunset district, recommended by a friend who uses the nearby public golf course. The Tee-Off (3129 Clement St, +415 752 5439) has no apparent dedication to the sport, though every other pursuit is represented by the mass of sporting detritus and there's even a ping-pong table in the backyard. It did have an elderly Chinese lady drinking at the end of the bar who swore vehemently at the bar's chef (the decent-looking menu includes ostrich and kangaroo) for no apparent reason. The barfly next to her responded with a line Humphrey Bogart would have been proud of: "Watch your language, I got a picture of my wife in my wallet."

San Francisco's famed Tonga Room features indoor rain showers in its tiki-themed splendour. The dive bar equivalent is Trad'r Sam (6150 Geary Boulevard, +415 221 0773) - no one knows what happened to the "e" - which features enough bamboo to choke a panda and, as an impressive touch, a pinball machine themed around Johnny Mnemonic - a terrible pre-Matrix Keanu Reeves film that hardly deserves to be eulogised in an arcade game).

The Li Po Cocktail Lounge in Chinatown (916 Grant Avenue, +415 982 0072) is almost too decadent to qualify as a dive, featuring golden lions, beautiful Chinese murals and enormous paper lanterns, but it still definitely has the appropriate edge of desperation.

I moved over to nearby North Beach, former home of the beats and visited The Saloon (1232 Grant Avenue, +415 989 7666), one of the city's oldest bars: it survived the earthquake and fire of 1906, which is also possibly when the toilets were last cleaned. Some kind of celebration was in progress as a large gathering of the area's beat types rallied around a lady in a wheelchair. I asked if it was a birthday party. "Quite the reverse," a patron told me. He revealed that it was in fact the last hurrah of "Rebel", former long-time bartender (rumoured to be the oldest in San Francisco), who was having a last tipple at her favourite establishment before heading to the great dive bar in the sky. I joined the locals for a drink in her honour.

With the sombre tone now established, I ventured into the Tenderloin district. Most travel guides have a simple message concerning this area of the city: avoid. But though it's home to many of the city's homeless and dispirited, it also possess some of the its premiere dive establishments. Aunt Charlie's (133 Turk St, +415 441 2922, auntcharlieslounge.com) purports to be a transvestite bar. Not much evidence of that, but there were plenty of men slavering over the baseball on the TV. If you like your dive bars dark, this is the place for you. The entire joint seems to be lit by the pink neon sign that says Aunt Charlie's. I tried sneakily to take a picture of it and my camera flash went off. "Who the hell is taking pictures in here?" asked Robert, the dapper and ancient barman. "You must be a cop," a barfly levelled at me. I trowelled on my most affected English accent in an attempt to appease, then quickly made my excuses and left.

I headed to the Ha-Ra Club (875 Geary St, +415 673 3148), one of San Francisco's most notorious dives. Everyone has a story about the Ha-Ra's legendary bartender Carl, who is part WC Fields and part Victor Meldrew. He doesn't like young hipsters cluttering up his joint. In fact, Carl doesn't really like anybody. "I've got good news and bad news," he told me as I arrived. "Good news, I'm still here. Bad news, I've only got Bud, Miller and ... Larry?" I was still wondering what sort of brew Larry could be when I realised that he'd stopped talking to me and was haranguing someone on the phone.

Everything is in place at the Ha-Ra. A bar, a television, a pool table. No DJs, no gourmet food, no espresso machine and no merchandise. Just a room, booze, and a slight air of despair. As I left, Carl yelled, "Have a good weekend!" at me. I was several blocks away before I realised it was Tuesday.

Coming full circle, I returned to the Mission for my final, and favourite dive, The Attic (3336 24th St, +415 643 3376). Dark and simple, The Attic has a thin strip of a bar, and a murky room beyond. It loses points for featuring DJs, but recoups some by not having a television (or even a phone). It's friendly, occasionally rowdy, totally unaffected and an excellent place to collapse in a corner and consider the world, which, after 18 hours of dive bars, seemed the sensible thing to do.