Michael Coveney: Barbican scales heights in downtown Dalston

Like all the best art shows, it’s ever so simple while remaining utterly puzzling. The Argentine artist Leandro Erlich has created a facade of a Victorian terrace house at ground level, with realistic painting of bricks, sills, a doorway and windows, and erected a huge similar-sized mirror tilted at 45 degrees above it; you can then walk across the surface, or lie down in the cavities and indents and this creates a curious random spectacle of people defying gravity, walking along walls, diving downwards, and generally carrying on like Superman on a night off.

Although right next to the Arcola – and you could pop into (or rather, up to) the house while catching Mike Weller’s brilliant two-hander, Fifty Words, in the Arcola itself – “Dalston House” is actually part of the Beyond Barbican summer season which was launched last night with a rooftop party, suitably enough, in the Dalston Roof Top.

This is a stunning new open air destination bar at the top of the Print House on Ashwin Street which in itself was worth discovering as part of Beyond Barbican: a sky-high oasis of greenery, bedding plants and mini-allotment frames with a music platform, two bars and spectacular views over Hackney’s Victorian buildings and the city skyline beyond.

Barbican general manager Nick Kenyon declared that London was moving east, justifying, reasonably enough, his organisation’s off-piste activities in Haggerston, Hackney and Shoreditch with a renewal of the Olympic spirit and a re-opening of the Olympic park with a two-day mini-festival. Louise Jeffreys, Barbican director of programming, was chuffed to announce an event in Leytonstone Library, right next door to where she lives.

It’s interesting, this urge of arts institutions to want to renew themselves by pushing at their own walls. I’d never even heard of the Rose Lipman Building in De Beauvoir Town, Haggerston, or indeed of Haggerston, and suddenly everyone’s going there. Well, by everyone I mean the Royal Court and now the Barbican and their audiences.

This week Theatre-Rites open a new show there as part of Beyond Barbican, and next week Toby Jones and Imelda Staunton open in a new play, Circle Mirror Transformation, as part of Vicky Featherstone’s inaugural Open Court season.

You have to be quick, or at least very keen, or you miss these things. The Greenwich and Docklands International Festival, for instance, has been going on for a week, and there’s even a beached whale somewhere, the one who swam up the Thames by mistake in 2006 (must be a bit high by now, surely?), as well as the usual stock of fireworks and acrobats. I’ve decided to take pot luck on Friday afternoon and sample a High Street Odyssey through what is described as a valley of bollards, benches and big brand names.

As a theatregoer, you could spend your entire life not going to theatres these days. And that, of course, is the point of companies like Punchdrunk, or the great spectacular outdoor theatre companies of the hippie heyday such as Welfare State and their successors, Kneehigh and Footsbarn, though Emma Rice of Kneehigh has been showing alarming tendencies of late in going “legit” within various proscenium arches.

Beyond Barbican is a good initiative because it defines the arts centre’s relationship with its environment in new and different ways. The commercial relationship with the city has always been at the heart of its operation, but in reanimating its roots in Stratford East (there has long been an affiliation with the Theatre Royal out there) and the boroughs in-between, it makes that relationship more culturally meaningful. And, let’s face it, more exciting.

Well, it felt a bit like that, anyway, on the Dalston Roof Park last night, under what looked like a suspiciously promising summer sky, to the accompaniment of funky music, calorific canapes and deliciously fruity cocktails.