IPAs, or India Pale Ales, have their origins in 18th-century England, when pale ales started being exported to colonialists in India; the bitter beers benefiting from weeks of conditioning aboard ship. So the story goes.
The modern version, with its big citrus and tropical flavours, however, has its roots in the US, as does its bigger and bolder brother, the Double IPA.
Legend has it that the first Double IPA came from the Russian River Brewing Company, in 1994, and was borne out of accident. A self-doubting brewer doubled up on his malts and his hops. Tasting it a few weeks later found he had brewed one helluva potent beer. Its descendent, Pliny The Elder is widely regarded as one of the world’s best beers, though it's almost impossible to source in the UK.

While the IPA has been at the vanguard of the renaissance in beer and brewing, persuading people away from bland pilsners and lagers, the Double IPA has largely lurked menacingly in the shadows. 
These are big beers, upwards of 7.5% in strength and with a bitterness that'll make you look like you're sooking on a straw. 
The best ones are rounded and balanced; heavy on the bittering but with enough malt sweetness, character and aromatic hops to give a beautiful, enjoyable and potent beer.

 

FIVE GREAT DOUBLE IPAs

Double Joker by Williams Brothers (8.3%) 
Like Pliny, Double Joker was borne out of an accident, though this time on Twitter when folk misread a Williams tweet that said "Double Joker brew day". So the story goes. The light aroma on Joker's big brother belies its potent, generously hopped lip-smacking bitter taste. Lush flavours of summer rain balance well with rich sweet malt flavours to a long bitter and boozy finish.

 

Ragnarok by Fyne Ales (7.4%)

Fyne Ale’s massively successively Jarl was given a mighty upgrade last year. While Ragnarok’s supposedly Jarl on steroids, it's very different to its bright wee brother. The aroma is melon, apricot and booze-soaked toffee and spices. It pours clear and golden, while the taste is a frenzy of oven-roasted fruits, spices, sweet malt and a residual bitterness that underlies everything.

 

Torpedo by Sierra Nevada (7.2%)

A classic US double IPA, and fairly easily available ... in big cans! Aroma of grapefruit does little to warn you of the explosive impact when you take a drink. Bursts with a big citrus flavours - more grapefruit, some lemon - and toffee malts. Bitterness stays with you like a piece of shrapnel in your belly.

 

Carrie by Kaapse Brouwers (6.5%)

Pedants might splutter at the inclusion of such a "weak" beer but this Dutch beer slips in under the fence for its big flavours and boozy character. Carrie pours a murky burnt orange, and tastes complex and enjoyably bitter, with tropical fruit flavours and plenty of caramel malt sweetness to balance this tangy beer. Hints of barnyard and the sea in this big, yet gentle, beer.


Double Axe by Buxton (10%)

A bruising belter, and another souped-up version of a classic beer (though weaker than an earlier offering). Double Axe is the big version of Axe Edge, itself a big, bold beer. Vibrant, powerful and embracing, Double Axe wraps itself around you and does not let go. Like an axe handle, the robust caramel malts hold it all together as the bittering and alcohol causes carnage and pungent aromas of tropical fruits and pine forest emanate from the US hops.

Images courtesy of Hippo Beers and Williams Brothers