This is a term that has certainly shrunk in the laundering: the reality is bounded by barbed-wire coils or by an eight-metre high concrete wall. What we are talking about is no broad area, but rather one in which the Palestinians are to be closely confined, locked in enclaves with limits marked by the Green Line and the new `separation fence' (q.v.) that has been built to its east. Within these enclaves are Palestinian villages and land now utterly cut off from the continuum of Palestinian life in the West Bank. Thus, for example, the seam area includes considerable stretches of Palestinian agricultural land whose owners live in the West Bank proper and now need special permits – not always available to them – in order for them to be able to work those lands or harvest their olive crops. At the same time, Palestinians who live in the seam area find themselves needing permits to leave and come back to their own homes (q.v. `illegals' in their own homes). There can be no doubt but that the existence of the `seam area' has seriously damaged the quality of everyday Palestinian life.
After the Second Intifada broke out in 2000, Israel decided to prevent passage between the West Bank and Israel which had been free for over 30 years, by putting up a separation barrier (electronic fence and wall with patrol roads). Its route did not adhere to the ‘green line’ but rather wound its way in many places and penetrated the West Bank in order to leave as many settler colonies as possible inside Israel, as well as large areas for their expansion.
The area caged between the fence and the ‘green line’ is named the seam zone. It contains the enclaves of Jewish settlements that are near the ‘green line’ (such as Alfei Menashe and Elkana), about 12 Palestinian villages disconnected from the West Bank by the fence, and vast farmlands belonging to Palestinian villages and disconnected from them by the fence. In total, the seam zone contains about 140,000 dunams of Palestinian farmlands, constituting about 12% of all the potential farmland in the West Bank.
Palestinians are not allowed to enter the entire seam zone without a permit, although it is an occupied area that has not been annexed to Israel, whereas Israelis and even tourists may move in it freely.
Read more about the PERMIT REGIME OF THE SEAM ZONE - https://www.machsomwatch.org/en/node/69323/.