Masjid Quba is one of Medina's essential religious sites, traditionally revered as the first mosque founded by the Prophet Muhammad after the Hijra. The present mosque is modern and expansive, but the importance of the site comes from that early Islamic memory rather than from age of fabric.
For pilgrims and Muslim travellers it has devotional weight; for others, access and etiquette depend on local rules and religious context. Its place south of the Prophet's Mosque also gives a useful sense of how Medina's sacred geography extends beyond the immediate central sanctuary.