Maps of the routes have been released. The second day's is a 218km round trip; Belfast to Antrim, Ballymena, Bushmills then taking in the Causeway Coastal Route from Cushendall to Larne onto Whitehead and Carrickfergus before returning to Belfast.
An aspect of the map I like is the elevation guide. I have thrown it on its side to suit the format of this blog. You can see these maps and the others at this link.