At one glimpse, you may think that this building is either a factory or an apartment building being built to cater for the need of local people who stay at the suburb of a small town. However, if you take a closer look at the overall structures and it's functionability, there is no way that human being can ever stay or live inside the building. There is no window or proper ventilation to the building.
Believe it or not, this is a house that has been built specifically for swiftlet walet. It's a house for the industry of bird's nest. In Asia, the walet industry has been highly commercialised due to the increasing demand of specially processed bird's nest for consumption and medicinal purpose especially among the Chinese culture.
In Malaysia, this typical bird's nest building can be seen along the main road of the east and west coast of the peninsular. Take a closer look at the nest in the following video.