Hadith 7074
Nafi' reports: Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) used to diligently seek out the relics of the Prophet Muhammad (peace be upon him). Every place where the Prophet (peace be upon him) had camped, Sayyiduna Abdullah (may Allah be pleased with him) would also camp there. The Prophet (peace be upon him) had once camped under an acacia tree, so Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) would bring water and pour it at the root of that tree so that it would not dry up.