Rambam - Hilchot Beit Habechirah 7:14c The Laws of God's Chosen House CITY WITHOUT CERAMICS OR CHICKENS - No Smoking. Ban on Birds. More of the limitations imposed due to the prominence and pragmatism of best preserving the special status Judaism’s most Sacred City. Further to the previous episode, since Jerusalem hosts the Beit HaMikdash it must be maintained to best reflect the honour and dignity of this hallowed edifice as well naturally facilitate Temple-centric Mitzvot. In pursuit of maintaining a pristine Ceramic Kilns were proscribed due to the volume of Rising Smoke and the stone façade discoloration they might cause. The Raising of Chickens was banned as birds who do not fly forage in the dumps and can easily import ritual impurity. Interestingly, the logic behind this Jerusalem restriction led to the legislation of Province-wide Priestly Prohibitions!