Before revision:  Our analysis shows that Hi--C maps display a non-trivial multifractal spectrum.We introduce a simple analytical model that describes the structure of chromosomes as a hierarchical set of domains nested in each other and we solve it exactly.
After revision:  Our analysis shows that Hi--C maps are bifractal, i.e. they are complex geometrical objects characterized by two distinct fractal dimensions. To rationalize this observation, we introduce a model that describes the structure of chromosomes as a hierarchical set of domains nested in each other and we solve it exactly.