Critic's choice: Top five exhibitions

Mark Wallinger: State Britain
Tate Britain, SW1
Remember the anti-war protestor who parked himself in Parliament Square until he was moved on by an act banning unauthorised demos within a onekilometre radius? Brian Haw actually began his campaign in 2001, when his beef was with economic sanctions, and over a five-year period built up a dense wall of placards and banners and longer rants, complete with a tea-making area and tarpaulin to keep him dry.
Mark Wallinger has recreated it with pernickety precision, kettle and all, in his latest installation.
Taken literally, the exclusion zone apparently bisects Tate Britain, and to emphasise his point, he's marked a line along the gallery floor.
It's neither subtle nor imaginative, but fans will no doubt be eager to see what Wallinger has been up to since his last major London project in 1999 - a lifesized Christ for Trafalgar Square's Fourth Plinth.
(020 7887 8888) Until 27 August.

LAST CHANCE: Velazquez
National Gallery, W1
When the great Spanish artist Diego Rodriguez de Silva y Velazquez became Philip IV's court painter in his early 20s, he entered a world of pomp and glamour whose rich colours ( a great antidote to winter's greys ) suffuse this careerspanning exhibition.
Yet Velazquez was hungry for realism, and his subjects number not only kings and courtiers, but also the crippled and the cripplingly poor.
That same appetite led him to develop an abbreviated, economical style that would later inspire the Impressionists and Picasso.
The National Gallery's own impressive holdings are enhanced by loans from the Museo del Prado, making this a rare last chance to see almost half of his surviving paintings at once. (020 7747 2885). Until 21 January.

LAST CHANCE: David Smith
Tate Modern, SE1
The late American sculptor David Smith was influenced by Picasso and Giacometti, yet the blood of his engineer father flowed thickly through his veins.
He grew up fascinated by railway tracks and locomotives, and in his teens took a job as a welder and riveter in a car factory, forging a life-long respect for heavy metals like steel and iron.
The monumental metal sculptures that he went on to make describe America's shift from an agricultural to an industrial society, but they also pack a surprisingly powerful emotional punch, evoking the wide-open spaces of his Midwestern roots.
A timely tribute to a prolific talent, whose life was sadly cut short in 1965. (020 7887 8888). Until 21 January.

LAST CHANCE: Turner Prize
Tate Britain, SW1
So we know who the winner is, and the shock of it being a painter (German-born Tomma Abts) has finally worn off, but did the judges get it right? There's still time to decide for yourself by taking one last look at work by all four nominees.
Rebecca Warren's rude, lusty sculptures in clay and bronze are flanked by vitrines filled with pom-poms and pink neon lights. Phil Collins's canny films feel ever more timely, catching up with people whose lives have been ruined by reality TV.
And Mark Tichner, who's best known for his outsize text works, he turns instead to wooden sculptures and film to express them.
Meanwhile, the winner has created an installation of abstract yet disciplined canvases in a characteristically muted palette. (020 7887 8008). Until 21 January.

LAST CHANCE: David Hockney Portraits
National Portrait Gallery, WC2
This bravura blockbuster has been so successful that the NPG will be open until midnight tomorrow to accommodate all those who failed to see it in the run-up to the holidays.
Spanning five decades and over 150 works, it's a joyous survey that more than confirms David Hockney's status as a national treasure. It's also a reminder of just how daring he was when he started out.
Back when Pop and Minimalism ruled, he devoted himself to realist painting, creating a solid body of full-figure portraits at once intimate and iconic, glamorous and poetic, often incorporating openly gay themes.
Mr and Mrs Clark and Percy is among the famous highlights, but images of the artist's mum and dad and Andy Warhol are equally striking. Catch it while you still can.
(020 7306 0055). Until 21 January.