Akira Kanayama Al Gebra Alec Finlay And While London Burns audiowalk biennales Bruce Nauman Catherine Yass Chloe Regan Christian Edwards Conor McGarrigle Dara Birnbaum David Bate dog walkers environment everyday Fiona Robinson footprints Francis Alys Franko B Hamish Foulton Hans Ulrich Obrist Ingrid Pollard Jan Estap Janet Cardiff Jeremy Deller Keith Arnatt Krzysztof Wodiczko Lawrence Abu Hamdan Long March Project marches Marcus Coates Marina Abramović Matthias Sperling Melanie Manchot Mona Hatoum museums Oleg Kulik participation peripatetic Peter Liversidge philosophy procession Regina José Galindo Richard Long Rut Blees Luxemburg Simon Faithfull Simon Pope Siobhan Davies Studios slapstick Sophy Rickett Susan Stockwell Tim Edgar Ulay walking