Sayyiduna Anas bin Malik (may Allah be pleased with him) said: We were in Madinah; when the mu'adhdhin called the adhan for Maghrib, the people would hurry to the pillars of the mosque and offer two rak'ahs, so much so that if a stranger entered the mosque, he would think, because of the great number of people praying those two rak'ahs, that the prayer had already been offered.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 4497