We've been following the developments at the Tate Modern's ongoing extension keenly – and not least because our London HQ conveniently overlooks the site. This is famously one of the world's most visited galleries of contemporary and modern art, and a prime London cultural destination since the former Bankside Power Station's transformation by Swiss duo Herzog & de Meuron opened its doors at the turn of the millennium.

Now, 16 years later, Herzog & de Meuron have returned to the site, adding a much-needed extension to the original brick structure built by Sir Giles Gilbert Scott prior to his death in 1960. Design development in the new wing began in 2009 and, come June this year, the building will throw open its doors to the public for the first time since the sneak peak offered by the brief reveal of the Tate tank galleries back in 2012.

This move will allow the Tate to display much more of its growing collection. Four floors of the new wing will be dedicated to exhibitions from the permanent collection, while, for the moment at least, temporary shows will remain in their original spaces.

The Tanks will also reopen and, spanning ten floors above them, the new extension will include a restaurant and bar, office space, the aforementioned galleries, a members room, and an accessible panoramic viewing level at the very top.

The fifth floor will play host to Tate's latest special project – the Tate Exchange. This innovative space will be dedicated to 'exploring wider social issues through art', explains the art institution. The Tate describes the Exchange as a 'modern experiment', which will provide space for interactive events and dialogue between artists, associates and the public.

The Tate Modern extension will launch on 17 June with a special weekend program of music, film, tours, workshops and events throughout the building.