Hadith: There is a gate in Paradise called Ar-Rayyān through which only those who fast will enter on the Day of Resurrection. No one else will enter through it. It will be called out: Where are those who used to fast? So they will stand up and proceed towards it. When the last of them has entered, the gate will be closed, and no one else will enter through it

عن سهل بن سعد رضي الله عنه عن النبي صلى الله عليه وسلم قال: ««إن في الجنة بابا يقال له: الرَّيَّانُ، يدخل منه الصائمون يوم القيامة، لا يدخل منه أحد غيرهم، يقال: أين الصائمون؟ فيقومون لا يدخل منه أحد غيرهم، فإذا دخلوا أغلق فلم يدخل منه أحد»
[صحيح] - [متفق عليه]

Sahl ibn Sa‘d (may Allah be pleased with him) reported: The Prophet (may Allah's peace and blessings be upon him) said: "There is a gate in Paradise called Ar-Rayyān through which only those who fast will enter on the Day of Resurrection. No one else will enter through it. It will be called out: ‘Where are those who used to fast?’ So they will stand up and proceed towards it. When the last of them has entered, the gate will be closed, and no one else will enter through it.'"
[Authentic hadith] - [Narrated by Bukhari & Muslim]

Explanation

The Hadīth informs that there is a door in Paradise called Ar-Rayyān which is exclusive for the fasting people. On the Day of Resurrection, the angels will call out those who used to fast - obligatory and voluntary fasts - regularly and ask them to enter through that door; and when they have entered, the door will be closed and no one else will enter through it after them.