Resonance chains have been observed in many different physical and mathematical scattering problems. Recently numerical studies linked the phenomenon of resonances chains to an approximate clustering of the length spectrum on integer multiples of a base length. A canonical example of such a scattering system is provided by 3-funneled hyperbolic surfaces where the lengths of the three geodesics around the funnels have rational ratios. In this article we present a mathematical rigorous study of the resonance chains for these systems. We prove the analyticity of the generalized zeta function which provide the central mathematical tool for understanding the resonance chains. Furthermore we prove for a fixed ratio between the funnel lengths and in the limit of large lengths that after a suitable rescaling, the resonances in a bounded domain align equidistantly along certain lines. The position of these lines is given by the zeros of an explicit polynomial which only depends on the ratio of the funnel lengths.and N n1,n2,n3 := {s ∈ C, P n1,n2,n3 (e −s ) = 0}where the zeros are repeated according to the multiplicities. Then for any bounded domain U ⊂ C with ∂U ∩ N n1,n2,n3 = ∅ we have lim ℓ→∞ # U ∩ Res n1,n2,n3 (ℓ) = # U ∩ N n1,n2,n3 .Note that U can be chosen arbitrarily small, so Theorem 1.1 states that a finite number of resonances is determined by P n1,n2,n3 at an arbitrary precision for large enough ℓ. As N n1,n2,n3 is the zero set of a polynomial in e −s , this set naturally forms straight chains in the sense that s 0 ∈ N n1,n2,n3 ⇒ s k = s 0 + 2πik ∈ N n1,n2,n3 , ∀ k ∈ Z.