One of the easiest items to 3D print are models of buildings. Their shapes are often straightforward for successful printing and yet quite recognizable. It's a great feeling when you print a building, give it to someone and they immediately recognize what it is without being told.
But the question is, where do you find 3D models of buildings? You could make them yourself, but obviously it's a lot easier if you can find them pre-made. While there are lots available from Google's 3D Warehouse, we've located another interesting repository of around 500 buildings that can be downloaded at no charge. Each building includes information and images, but sometimes they include 2D drawings and also 3D models.
One problem with this particular repository is that the models are stored IN .3DMF, which is a very old format not typically used in recent apps.
Remember, though, that you should visually inspect your prospective model to ensure it's truly printable. Large overhangs are not desirable unless your printer and software can place support material.