Eruvin 60A

ולא עירבו, אם יש לפניהם דקה ארבעה ⁠— אינה אוסרת, ואם לאו ⁠— אוסרת.

and did not establish a joint eiruv, if there is a partition 4 handbreadths wide in front of the entrance to the balcony, the balcony does not prohibit the residents of the courtyard from carrying, as each area is considered to be independent. And if not, the balcony prohibits the residents of the courtyard from carrying in the courtyard. This indicates that a ladder between two courtyards is always considered an entrance, even when that policy leads to a stringent ruling, unless the two areas are separated by a partition.

הכא במאי עסקינן, בדלא גבוה מרפסת עשרה.

The Talmud answers: With what are we dealing here? With a case where the balcony is not 10 handbreadths high from the ground. Consequently, it does not constitute a domain in its own right, and it is part of the courtyard.

ואי לא גבוה מרפסת עשרה, כי קא עביד דקה, מאי הוי? במגופפת עד עשר אמות, דכיון דעביד דקה ⁠— איסתלוקי איסתלוק ליה מהכא.

The Talmud asks: If the balcony is not 10 handbreadths high and is therefore part of the courtyard, when one places a partition, what of it? The balcony should nevertheless be considered part of the courtyard. The Talmud answers: We are dealing here with a balcony that is entirely fenced off except for a section up to 10 cubits wide, which serves as an entrance. In that case, since the residents of the balcony place a partition at this entrance, they thereby remove themselves entirely from the courtyard.

אמר רב יהודה אמר שמואל: כותל שרצפה בסולמות, אפילו ביתר מעשר ⁠— תורת מחיצה עליו.

Rav Yehuda said that Shmuel said: With regard to a wall that one lined with ladders, even along a length of more than 10 cubits, it still retains the status of a partition. The ladders do not constitute an opening that is more than 10 cubits wide, which would cause the wall to be regarded as breached and would invalidate the wall as a partition.