The Messenger of Allah (may Allah's peace and blessings be upon him) ordered us to build mosques in different localities and that they should be kept clean
Authentic hadithعن عائشة رضي الله عنها قالت: أَمَر رسول الله صلى الله عليه وسلم بِبناء المساجد في الدُّورِ، وأن تُنظَّف، وتُطيَّب.
‘Ā'ishah (may Allah be pleased with her) reported: The Messenger of Allah (may Allah's peace and blessings be upon him) ordered us to build mosques in different localities and that they should be kept clean and perfumed.
Explanation
The Messenger of Allah (may Allah's peace and blessings be upon him) ordered that mosques to be built in different neighborhoods, i.e. every neighborhood should have a mosque. They should also be cleaned from all dirty and filthy things. They should also be perfumed with incense and other things that have good scents.
Source · Narrated by Abu Daoud
From the Hadith Encyclopedia (hadeethenc.com).