Perhaps you know remove the shoes when get into a house in Japan.

But it is not normal to remove the shoes when you get into a house. When you go up to Agedoko (raised floor), you must remove the shoes. This Agedoko style construction is able to find in almost all houses even in an apartment. Originally, Japanese spend major time on the floor such as spleeping mat Futon, etc. So Agedoko is a way not to bring in outside dust into the house. Agezoko makes dead space under the floor but it is not dead. The space uses for storing space, maturation of preserved food, etc.