This Article is the first to systematically consider the Constitution’s identification, definition, and integration of the physical spaces in which it applies. Knowing how the Constitution addresses a particular problem often requires knowing where the problem arises. Yet despite the importance and pervasiveness of spatial references in the Constitution, commentators have not analyzed these references collectively. This Article fills that gap in the literature by examining each of the fourteen spaces that the Constitution identifies, as well as several that it overlooks, to reveal patterns in the text’s treatment of space and location. Among the spaces that the Article considers are "the Land" referenced in the Supremacy Clause, the "United States," "States," "Territory," "Property," the District of Columbia, federal enclaves, vicinage "districts," the "high Seas," "admiralty and maritime Jurisdiction," Indian lands, national airspace, and underground resource deposits. The Article shows that many discrete problems on which scholars have focused - such as the rights of U.S. military detainees abroad, the role of federal law on Indian reservations, and the extraterritorial reach of state law - are manifestations of a broader phenomenon that exists because of indeterminacy in how the Constitution allocates power over different kinds of spaces. Considering the many distinct kinds of constitutionally defined and constitutionally overlooked spaces together highlights this indeterminacy, provides new perspectives on commonly discussed problems, and exposes additional puzzles that have escaped scrutiny. The Article makes four basic points on which future scholarship can build. First, although the Constitution creates a typology of spaces that relies on formal categories, the categories often have little utility in resolving specific questions. The text’s description of the physical contours of spaces and the legal significance of their borders is too imprecise to permit a jurisprudence of labels that converts lines on a map into "bright line" rules of decision. Determining where in physical space a problem arises is therefore a necessary but insufficient prerequisite to determining which government entities can address the problem and how they may respond. Second, constitutionally defined places routinely overlap, such that a point in physical space can map onto several points in constitutional space. Drawing conclusions about how the Constitution regulates particular spaces in particular contexts therefore requires developing rules for allocating concurrent authority and resolving competing claims. Third, even when spaces do not physically overlap, events in one space routinely have consequences in others, residents of a space routinely act in others, and agents of an entity that controls a particular space often operate in other spaces. These spillovers raise questions about when entities (such as states, the United States, and tribes) can regulate beyond borders that would normally cabin their jurisdiction. The parameters of a constitutionally defined place are thus not necessarily coextensive with the reach of an entity governing that place. Finally, the same questions tend to recur in multiple spatial contexts. For example, who decides the boundary of a space and by what standards, when can federal courts create common law governing a space, and when does the text’s explicit enumeration of a space’s attributes imply by negative implication the absence of other attributes? Exposing how these questions arise in multiple contexts reveals subtle dimensions of problems that can go unnoticed when viewed in isolation. The pervasive and overlooked "where" question in constitutional law therefore merits systemic scrutiny
