Different methods for making sure the entryway to an alleyway is not wider than 10 amot, application to a section of an eruv that could not be used as an entrance because it had field mines

The status of the space in between the side-posts, the logic of min b'mino v'neior, guard duty on shabbat and minimizing prohibition, deeper idea behind this principle

The status of a body of water in the construction of an eruv

Following 2 chumrot/stringencies or kulot/leniences in halacha

The parameters of a reshut harabim: width of roads, 600,000 people- all at one time? In one day? On one street? In one city? Does it include visitors/non-residents?

What is the maximum permitted width of a breach in the wall of an alleyway to maintain its status of a place that can be carried within it, the new status of chatzer and mavui in the days after the Talmudic era

The special limmud of Eruvin to bring mashiach, the principle of lavud in the laws of eruvin and in what cases it may not/may not be applied

The principles of Eruvin are modeled after Torah structures of Sukkah and the Beit Hamikdash, the principle that we are more lenient in certain cases within a group because the group members can remind one another of possible halachic violations

The difference between a korah- crossbeam and a lechi- side-post, the deeper idea behind the institution of eiruvin and introduction to the masechet

How could Rabbah bar Rav Huna be measuring the water in his bathtub even if it was only mitasek? Closing thoughts on masechet Shabbat