  Seiberg-Witten geometry of mass deformed $\mathcal N=2$ superconformal ADE
quiver gauge theories in four dimensions is determined. We solve the limit
shape equations derived from the gauge theory and identify the space $\mathfrak
M$ of vacua of the theory with the moduli space of the genus zero holomorphic
(quasi)maps to the moduli space ${\rm Bun}_{\mathbf G} (\mathcal E)$ of
holomorphic $G^{\mathbb C}$-bundles on a (possibly degenerate) elliptic curve
$\mathcal E$ defined in terms of the microscopic gauge couplings, for the
corresponding simple ADE Lie group $G$. The integrable systems $\mathfrak P$
underlying the special geometry of $\mathfrak M$ are identified. The moduli
spaces of framed $G$-instantons on ${\mathbb R}^{2} \times {\mathbb T}^{2}$, of
$G$-monopoles with singularities on ${\mathbb R}^{2} \times {\mathbb S}^{1}$,
the Hitchin systems on curves with punctures, as well as various spin chains
play an important r\^ole in our story. We also comment on the
higher-dimensional theories.
