  Real flag manifolds are the isotropy orbits of noncompact symmetric spaces
$G/K$. Any such manifold $M$ enjoys two very peculiar geometric properties: It
carries a transitive action of the (noncompact) Lie group $G$, and it is
embedded in euclidean space as a taut submanifold. The aim of the paper is to
link these two properties by showing that the gradient flow of any height
function is a one-parameter subgroup of $G$, where the gradient is defined with
respect to a suitable homogeneous metric $s$ on $M$; this generalizes the
Kaehler metric on adjoint orbits (the so-called complex flag manifolds).
