Extending the private domain via the boards around the well, which fundamentally come to include it - and the limitations on this extension. There's a need for access to water - for animals, for people on a pilgrimage to Jerusalem, etc. And on this daf, that measure of specificity comes into play. Also: Those limitations become even clearer in the context of "burganim," watchman's towers, and whether they were allowed outside of the Land of Israel... And whether those well extensions were permitted in an area that did not have yeshivas, to justify their use by those in pursuit of a mitzvah (learning Torah). Also: the rabbinic enactments get a big push on this daf, using verses to present how important they are. But if that's the case, shouldn't the rabbinic enactments be part of the Written Torah?! Yet, the Oral Torah has infinite expansive possibilities that go beyond the written word. Plus: Who's Who: The self-sacrifice of Rabbi Akiva for the sake observing rabbinic enactments (specifically, washing his hands before eating), and how he represents exactly the importance of rabbinic interpretation and application.