An eruv (Hebrew: עירוב‎ mixture) is a ritual enclosure that some communities construct in their neighborhoods as a way to permit Jewish residents or visitors to carry certain objects outside their own homes on Sabbath and Yom Kippur. An eruv accomplishes this by integrating a number of private and public properties into one larger private domain, thereby countermanding restrictions on carrying objects from the private to the public domain on Sabbath and holidays.

Here the map of venetian Eruv, click on it:

pianta