An electron antidot system is an open geometry problem and often requires heavy calculations to compute its physical properties. Such a difficulty can be avoided by transforming an electron antidot system to a system of hole quantum dot since the transformed system contains only a finite number of confined holes. Using this transformation, we present a microscopic approach to study electronic properties of an antidot in the integer quantum Hall regime. Based on this approach we discuss various conditions under which the Kondo effect may be present. (C) 2003 Elsevier B.V. All rights reserved.