Abstract: A plurality of arched rib supports is provided with each rib support being pivoted at the upper end or apex thereof so that the lower end portions may move towards one another. A flexible cover is secured to the rib supports and the lower ends are normally mounted upon a common locus so that the shelter can be opened in the form of a partial torus. When it is to be stored and/or transported, the rib supports are folded together to overlap one another, detached from the means pivoting same on a common locus and then the ends are moved towards one another so that they overlap with the gores of the flexible cover being between adjacent hoops. This reduces the overall size of the rib supports, and facilitates handling of the collapsed shelter.

Abstract: A shelter comprises at least two sets of arched support ribs with the support ribs of each set being pivoted by the adjacent ends thereof upon a common locus and having one set of support ribs over spanning the other set at an angle to each other. Some of the intersections are secured together and a flexible cover is secured over the support ribs. By situating the end support ribs in a plane at an angle to the supporting surface upon which the shelter is erected, substantially triangular openings are defined which can be used for access if required.