Mefulash: A Street Open From End to End
Mefulash describes a route open through from one end to another. Its precise application depends on the walls, gates, alignment, and city layout discussed by the poskim.
Open from one side to the other
Mefulash describes a route that passes through openly from one side to another. In a walled city, the classic picture is a public street running between opposite gates.
The precise application is debated: alignment, bends, the relationship between connected streets, and the status of the surrounding walls can all affect the result.
The ends of the route
A road opening into other public streets or continuing beyond the claimed enclosure differs from a lane that ends inside a genuinely walled area. Both ends must be located in the physical city, not inferred from a cropped neighborhood map.
Bridges, tunnels, and highway ramps can extend the public route through what otherwise appears to be a boundary.
The Yerushalayim discussion
In the meeting with Israel's Chief Rabbis, Rabbi Mordechai Eliyahu describes the curved streets of newer Yerushalayim. The Rebbe interjects lo mefulash, and Rabbi Eliyahu continues that this prevents the route from being de'oraisa according to his approach.
The direction of the streets is treated as an actual feature of Yerushalayim alongside their width, population, and surrounding walls.