The Last Crusade Mystery Cache

Hi Junior, take a look at this old crusader map. I discovered it from the Porvoo Cathedral catacombs and copied it to my diary. It is clearly a Knights Templar map with the rose sign. Map is called Occultus Thesa rus. Oh, my coffee mug. Occultus is either hidden or Secret and that Thesa rus could be Thesaurus and it means a treasure. This needs to be studied better. Strange places and lines. Is it possible that there is square angle between those two locations? Junior, could you help me in this. I have no earthly idea that how I can solve this.
Henry Jones