  It is known (E.L. Green (1997), O. Post (2003)) that for an arbitrary
$m\in\mathbb{N}$ one can construct a periodic non-compact Riemannian manifold
$M$ with at least $m$ gaps in the spectrum of the corresponding
Laplace-Beltrami operator $-\Delta_M$. In this work we want not only to produce
a new type of periodic manifolds with spectral gaps but also to control the
edges of these gaps. The main result of the paper is as follows: for arbitrary
pairwise disjoint intervals $(\a_j,\b_j)\subset[0,\infty)$, $j=1,...,m$
($m\in\mathbb{N}$), for an arbitrarily small $\delta>0$ and for an arbitrarily
large $L>0$ we construct a periodic non-compact Riemannian manifold $M$ with at
least $m$ gaps in the spectrum of the operator $-\Delta_{M}$, moreover the
edges of the first $m$ gaps belong to $\delta$-neighbourhoods of the edges of
the intervals $(\a_j,\b_j)$, while the remaining gaps (if any) are located
outside the interval $[0,L]$.
