Al-Buraq (البُراق) is a beautiful tall winged white steed from the Heaven which the prophets used to mount for visiting distant places in the twinkling of an eye.
The Holy Prophet Muhammad (ﷺ) travelled from Mecca (Masjid Al Haram) to Jerusalem (Masjid Al-Aqsa) and the various Heavens during the Isra and Mi'raj (الإسراء والمعراج) -the miraculous night journey on the Buraq.
On reaching Masjid Al-Aqsa, the Holy Prophet (ﷺ) tied Buraq to a ring of iron in a circle of high rock near the Al-Buraq Wall (حائط البراق) also known as the Western Wall. It is still there to this day and the Muslims have built a high dome over it.
Sahih al-Bukhari, 5:58:227 describes Al-Buraq as:
"... Then a white animal which was smaller than a mule and bigger than a donkey was brought to me." ... "The animal's step (was so wide that it) reached the farthest point within the reach of the animal's sight..."
In the Qur'an Prophet Muhammad (ﷺ)'s Night Journey to the Heavens is quoted as:
۞ سُبْحَانَ الَّذِي أَسْرَىٰ بِعَبْدِهِ لَيْلًا مِّنَ الْمَسْجِدِ الْحَرَامِ إِلَى الْمَسْجِدِ الْأَقْصَى الَّذِي بَارَكْنَا حَوْلَهُ لِنُرِيَهُ مِنْ آيَاتِنَا ۚ إِنَّهُ هُوَ السَّمِيعُ الْبَصِيرُ [١٧:١]
Glory to (Allah) Who did take His servant for a Journey by night from the Sacred Mosque to the farthest Mosque, whose precincts We did bless,- in order that We might show him some of Our Signs: for He is the One Who heareth and seeth (all things).
[Qur'an, Surah Al-Isra, Verse 1]
It is also said that Al-Buraq carried Prophet Ibrahim (عليه الصلاة والسلام) every morning to his wife, Hadrat Hajrah (رضي الله عنه), and son Prophet Ismail (عليه الصلاة والسلام) in Mecca. In the evenings, the Al-Buraq would carry Prophet Ibrahim (عليه الصلاة والسلام) back to Syria to his wife Hadrat Sarah (رضي الله عنه).