  Overlap fermions implement exact chiral symmetry on the lattice and are thus
an appropriate tool for investigating the chiral and topological structure of
the QCD vacuum. We study various chiral and topological aspects on
Luescher-Weisz-type quenched gauge field configurations using overlap fermions
as a probe. Particular emphasis is placed upon the analysis of the spectral
density and the localisation properties of the eigenmodes as well as on the
local structure of topological charge fluctuations.
