From Sahih Bukhari (Hadith 560):
Narrated Jabir bin `Abdullah:The Prophet (ﷺ) used to pray the Zuhr at midday, and the `Asr at a time when the sun was still bright, the Maghrib after sunset (at its stated time) and the `Isha at a variable time. Whenever he saw the people assembled (for `Isha' prayer) he would pray earlier and if the people delayed, he would delay the prayer. And they or the Prophet (ﷺ) used to offer the Fajr Prayers when it was still dark
Reference: Bukhari 560