Tat Dam ("black stupa"). It's right outside the embassy gates on a small road. It's really cool. Legend has it that the Tat covers a cave in which dwells a dragon that at some point in time helped the lao defeat the invading....thai, burmese, khmer, chinese, vietnamese, take your pick. I don't remember which, but at some point or another in history I think all the above-mentioned peoples have invaded laos. Anyway, not real long on details as you can see, but it's a cool stupa nonetheless. And it's right outside my office.