The SR-71 last flew on 9 October 1999. It is still the fastest air-breathing manned aircraft ever built.
Maximum speed of Mach 3.3 at 80,000 feet, and a ceiling of 85,000 feet.
There are some great documentaries on The Blackbird, but they are longer than I like to include here. This one is good, and it is only 8 minutes long.
If you have time, and the interest, look up some of the longer documentaries. This plane is an engineering marvel. There is a surprising amount of information available. The engines which (sort of transitioned) from regular turbo jet to ramjet are simply amazing.
I wonder what we can do, or what we are doing, with the technology available today.