This project investigates a specific concept within architecture: the portal. Divided into eight independent chapters, all possible to read as stand-alone parts, the thesis – a hybrid essay consisting of text, images, drawings and models – uses the portal as a springboard, or tool, for approaching existing theories on the invisible forces that shape the world and our built environment.    The chapter Nature approaches the portal and architecture as separator from "nature", the chapter Ritual as a ritual device for transition, the chapter Myth as a mythological archetype, the chapter Liminal as interstitial space and recursion, the chapter Depth as an enhancer of depth, the chapter Speed as a technological machine, and finally, the epilogue concludes that architectural practice in large can be interpreted as the creation of different types of portals.   Architecture, both as a subject and as a practice, has the potential to manifest and mediate between various supplementary relationships, such as interior and exterior, nature and culture, sacred and profane, heaven and earth, past and future, between sign and signified, us and them, between order and chaos, between subject and object, thought and action, private and public, rationality and imagination, flat and three-dimensional, flesh and matter (the list can go on forever).    The portal works both as an analogy for this and as an actual tool; partly by changing the character of adjacent spaces by such basic things as placing a door in a wall or placing a building in a landscape, but partly by finding new ways to bridge between extremities, without necessarily dissolving them completely.