A weather resistant portable pet shelter, including a rigid shell enclosing an interior space, the rigid shell including a lower base portion below the interior space having at least one external, downwardly facing element having a predetermined shape, a side wall portion extending at least substantially around the interior space and including a door opening connecting therewith, and an upper roof portion above the space and including a peripheral portion therearound having an external dish shaped structure defining an upwardly open concave region adapted for receiving and supporting a pet or a pet bed on the roof portion, the external dish shaped structure being configured for mating with and supporting the at least one downwardly facing element of the base portion such that a second pet shelter including the at least one downwardly facing element can be supported by the shell above the roof portion. The pet shelter can be configured for use as a pet entertainer, and also a carrier.