Majma al-Zawaid — Hadith 15126

Abu Harthamah said: I was with Sayyiduna Ali (may Allah be pleased with him) by the river of Karbala. He passed by a tree beneath which lay the droppings of gazelles. He took a handful of the soil from there, smelled it, and then said: "From here seventy thousand people will be raised on the Day of Gathering who will enter Paradise without any reckoning."
Imam al-Tabarani recorded it, and its narrators are thiqat (trustworthy).