Straight and Open Streets

Discussions of reshus harabim often refer to a street being “straight,” “open,” or running “from gate to gate.” These expressions come from several related halachic formulations, and they do not all describe the same requirement.

The clearest distinction is between mefulash, a route that runs through and opens onward, and mechuvan, aligned or directed opposite another opening. In the classical discussion of a walled city, both ideas can appear together. Elsewhere, a route can have the halachic character of a mefulash even though it bends.

Gate-to-gate alignment belongs to the discussion of a walled city

In Eruvin 6a, Rashi describes a reshus harabim as sixteen amos wide and, in the case of a city with walls, having its public route “mechuvan from gate to gate, so that it is mefulash,” comparable to the routes of the encampment in the Midbar. In his explanation of Yerushalayim, Rashi again refers to its reshus harabim as aligned from gate to gate and mefulash.

The Shulchan Aruch codifies the distinction in Orach Chaim 345:7. Streets and marketplaces sixteen amos wide can be reshus harabim where they have no surrounding wall. If the city has a wall, the Shulchan Aruch speaks of a route that is mefulash from gate to gate, together with the law of the city gates.

The Alter Rebbe makes the alignment explicit in 345:11:

שהם מפולשים משער לשער, דהיינו שהשערים מכוונים זה כנגד זה

“They are mefulash from gate to gate, meaning that the gates are aligned opposite one another.”

He then says that that route aligned from gate to gate has the law of reshus harabim when it is sixteen amos wide and the other stated conditions are present.

This is the primary source of the familiar language about a “straight” city route. The text is speaking about the alignment of gates and the road joining them inside a walled city.

Mefulash and straight are distinct terms

The Gemara itself supplies an important caution against treating mefulash as a synonym for geometrically straight.

Eruvin 6a discusses a mavo'i akum, a bent mavo'i. Rav says, “toraso kimefulash,” it has the law of a mefulash mavo'i. Rashi explains that its opening into the adjoining section is treated like a through-opening into reshus harabim for the laws then under discussion.

That sugya concerns the rabbinic requirements for permitting a mavo'i, and it should not be converted into a standalone definition of Torah-level reshus harabim. It nevertheless shows the terminology very clearly: a route can bend and still be treated halachically as mefulash in a relevant sense. Geometric alignment and through-connection are separate concepts.

Rashi's own language in the same daf reinforces the distinction. He uses mechuvan for the alignment from gate to gate and mefulash for the resulting open route.

The rule is different when there is no city wall

The wall matters because it changes what the gates and exits are doing halachically. The Alter Rebbe's 345:11 first describes streets and marketplaces with no surrounding wall. Only afterward does he discuss the special case in which there is a wall and the public route remains mefulash from gate to gate.

Rav Moshe Feinstein develops this distinction explicitly when discussing American cities. In Igros Moshe, Orach Chaim V, siman 28, he writes that in a city without a surrounding wall, where one can leave by the street network in many directions, the city's exit does not have to be aligned or mefulash in the same gate-to-gate manner. He applies this point specifically to Brooklyn and to American cities lacking such walls.

Rav Moshe's discussion is an interpretation and application of the earlier sources. It should therefore be cited as Rav Moshe's position rather than turned into a universal definition accepted in precisely the same form by every posek.

What a bend in a modern street does and does not establish

A bend can be significant when the shita being applied requires a particular route to be aligned, especially in the classical walled-city formulation. A bend can also affect whether one segment is properly considered a continuation of another.

At the same time, the sources do not provide a universal rule that every bend automatically destroys reshus harabim. Eruvin 6a uses the category of mefulash for a bent mavo'i in its own context. The Alter Rebbe's gate-alignment language is stated specifically within the walled-city case. Rav Moshe expressly distinguishes an unwalled modern city from that case.

Accordingly, a modern street cannot be classified from the word “straight” alone. The relevant questions are which source and category are being applied, whether the city is enclosed by walls, what the street opens into, whether it forms part of a larger public route, and which additional conditions for reshus harabim are present.