Organisers of the fifth Liverpool Biennial - Britain's largest contemporary arts festival - say it is a great success, more impressive in scale and ambition than any of its predecessors.

Over 40 artists from around the world are exhibiting works with the theme of "Made Up" in the international part of the festival, which also has its own independent fringe. There is no doubt the Biennial is a major event of the city's year as European Capital of Culture 2008, but some critics question whether there is enough local relevance and also argue that not all the exhibits are really "art".

Yoko Ono's Sky Ladders, a collection of decorators stepladders displayed in the ruins of St Luke's Church, has polarised opinions. Jasmin Maddock from the Stuckist Movement, which opposes the "pretensions of conceptual art", says "it's a joke." But the director of the Liverpool Biennial, Lewis Biggs, defended it as an inspirational highlight.

Our reporter Paresh Patel went on a guided tour with Laurie Peak, the Biennial's Director of Programme for Public Art.