We played our first games of TH on the weekend, and had a question about the Catacombs map. Certain colours, like Red, are used more than once in more than one area of the board, i.e. not on the same path, but across the board. Is FFG just recycling colours, or are the two, or more areas in line of sight?

It could be an higher area that allows to see others, but if that was: how do you calculate the number circle between your character and those area?

No, I think FFG just recycles colours.

The colors are being reused - see the new rules for a diagram of all circles...