Let \({\mathcal C}(X)\) be the \(\perp\)-closed subsets of a set \(X\) with a binary relation \(\perp\) which is irreflexive, symmetric and satisfies \(x^{\perp\perp}=\{x\}\). For \(A,B\in{\mathcal C}(X)\) the relation \(A\theta B\) holds iff \([A\cap B,\;A\vee B]\) is of finite height. It is shown that \(\theta\) is a congruence relation and \({\mathcal C}(X)/\theta=L\) is an orthomodular lattice. It is not 4-orthodistributive, has not the path property, is not locally finite, not modular, but is simple. The set of commutators is a full subalgebra of \(L\). \(L\) is not in one of the typical classes of orthomodular lattices.