Radio 4 Extra: From Mark Steel to Ira Glass, this little brother has some great material

The network dedicated largely to repeats is a treasure trove of broadcasting brilliance

Nostalgia isn't my thing. As a general rule, I'm more interested in what's happening now rather than dwelling on what happened half a lifetime ago.

This is why I didn't pay much attention to Radio 4 Extra (formerly BBC7 until it was rebranded in 2011), the network dedicated largely to repeats, when it first launched. It seemed to me to be the radio equivalent of the TV network, Gold, a channel that I only ever pause to watch if I want to be reminded of the crushing awfulness of Eighties comedy and give thanks that someone invented Friends.

And so comes the point where I realise I've had it all wrong. In the past 12 months, courtesy of Radio 4 Extra, I have basked delightedly in retrospectives of Chris Morris shows including Blue Jam and On the Hour, prompting me to wonder what sinkhole radio satire has plunged down since the Nineties.

I have boggled at the demented anarchy that is The Goon Show and the combined melancholy and mirth of Hancock's Half Hour, although I haven't made much headway with Steptoe and Son, possibly because it's not as funny if you can't look at Albert's gnarly old mug. The network has also brought us some terrific contemporary American shows, among them This American Life, presented by Ira Glass and the yardstick by which all other programmes about human experience are measured; TED Radio Hour, the weekly show built around the world of ideas; and the online mega-hit Serial.

Yes, it turns out that Radio 4 Extra is a treasure trove of broadcasting brilliance rather than a cupboard into which the corporation chucks programmes past their sell-by dates. Furthermore, its commissioners have shown themselves to have their fingers firmly on the pulse of international podcasting.

Who knew? Well, according to the latest Rajar figures, 2.17 million listeners a week knew. That's an increase of 500,000 listeners in the last quarter, which now makes it the biggest digital-only station in the country.

Clearly, 4 Extra isn't simply about exhuming long-forgotten shows as, for much of the time, it acts as a catch-up service. This week I heard Mark Steel's in Town, the series in which Steel, The Independent columnist, gets to know a town before affectionately taking the piss out of it in 30 minutes of stand-up.

In a programme first broadcast just a week previously on Radio 4, he was in Fleetwood in Lancashire, and among the delicious tidbits that he unearthed was that its greatest export, Fisherman's Friend lozenges, are beloved by Stevie Wonder; that it is the first town in the UK to publicly declare itself a "breastfeeding-welcome town"; and that its weekly institution "Tram Sunday" appears to be the only day that the trams don't run.

Archive on 4 also gets an airing on 4 Extra, which is just as it should be since it's one of the most consistently excellent documentary series on the radio and a jewel in the BBC back catalogue. This week's, entitled Some Like It Hot, was no different. First broadcast in 1999, it found Cleo Laine reassessing the legacy of the all-girl swing bands of the 1940s and talking to the now elderly female brass players who made a living touring the world and irritating the male musicians who thought they had live music all sewn up. Some things never change.

Twitter: @FionaSturges