A crossroads is nowhere in particular, which is exactly what several unrelated traditions have found useful about it. Ordinary space is organized by direction, a road leads somewhere and belongs to that route, but the point where roads cross belongs fully to none of them. It is the one common piece of everyday geography that a culture can point to and say: here the ordinary rule of orientation breaks down, and something else can enter.
Hecate's crossroads cult in ancient Greece put this to work directly. Three-way crossroads, triodoi, received a small shrine or a set meal left at the new moon, the Hecate's supper, and the goddess herself was imagined standing where the roads met, one face looking down each of the three ways, torch in hand, presiding over travelers, the restless dead and the practice of magic that ancient sources associate with her more than with any other Greek deity.
Legba's crossroads role, carried from Fon religious practice in the kingdom of Dahomey into Haitian Vodou as Papa Legba, works on a different logic but the same geography. He is not merely present at the crossroads, he is its guardian and its opener: in Vodou ceremony he must be saluted and asked to open the gate before any other spirit can be approached, because the crossroads is the point of passage between the human world and the spirit world, and nothing crosses it without his consent. Exu carries the same gatekeeping office into Brazilian Candomble and Umbanda under a different name, messenger and crossroads spirit both, and Pomba Gira, his frequent companion in Quimbanda, holds a related crossroads guardianship of her own.
Different traditions reach the same conclusion: a place with no direction suits a power that stands between two worlds rather than belonging to one.