Ha! I did something similar a few years ago. Was so sick and exhausted coming home from work that I just walked in the front door, into the living room, laid down on the floor and fell asleep. Woke up at 10:30pm, spent an hour cleaning up, feeding and paying attention to the cat, then went to bed and slept another 8-10 hours.
I flew to Irkutsk, spent two days there and flew home. I couldn’t adjust after I got home and didn’t sleep for a couple of days straight. My hubby took me to Urgent Care and they gave me some kind of seditive. I was out for 20 hours.
Approximately 90 hours, as I sat watch with my mother in the last days of her life. I slept on Friday night, no sleep from Saturday morning to Tuesday night. I slept only about 2-3 hours that night, maybe 4 hours the following night, and then Thursday night I came home and slept for 12 hours.
There is absolutely no way I could have done that without the extreme circumstance to fuel me. I truly did not feel the least bit tired, although I was a complete wreck mentally and emotionally.
At some point, maybe on Sunday or Monday (so after at least 30 hours), I began to have auditory hallucinations. (I would hear quiet music constantly, like it was coming from another room and I couldn’t quite make it out.) When she died at around 3 am on Tuesday morning, I was having visual hallucinations of blue and green colored lights floating in the room, like after-images that don’t go away.
12 hours after having been up for 40.
17 hours when I was 16 or 17 years old. I’d gone to bed at 1 am after smoking a lot of weed. I woke up at 6, and heard my dad on the phone ordering pizza. I was wondering how he was ordering pizza at 6 o’clock in the morning, and then I figured out that it was 6 pm. I hope they at least checked on me.
'Bout 20 hours. Got home one afternoon after a weekend of camping with my Boy Scout troop, fell asleep on the couch, and remained there until late morning.
Oh, damn me, I just realized I read the OP completely wrong.
BUT, I do honestly think that 12 hours of uninterrupted sleep is the longest I’ve ever had. So I guess I did answer the OP, only backwards. 
Irkutsk? Siberia? Just popped in for a weekend, or something?
You weren’t smuggling sable out, were you?
Whatever you were doing it should be worthy of a thread of its own.
24 hours, having been up for 48+. Travelling to far side of France from the West Coast of US.
-Bad storm on the East Coast, so airport was flooded. We were re-routed and had to take a bus to NYC. No flights out. Waited overnight and part of next day for a flight. No hotel. Sat around airport.
-Arrived in Paris. Went to train station, had missed all connecting trains. Sat around train station, also overnight. Finally caught a train. Arrived in Metz.
-Drove to village where I was staying and arrived around dinner time. Was welcomed. It was lovely. I was mortified when I fell asleep and woke up around dinner time the next day. 24 hours later. On the plus side, no jet lag.
I doubt I have ever slept 8 hours without waking up, I have had a few close to 24 hour periods where I stayed in bed and mostly slept.
About 20-22 hours, back when I worked nights. I would get off work Saturday morning and be asleep by 8AM. Sometimes I’d wake up to watch Saturday Night Live, go back to bed and wake up Sunday morning; sometimes I’d just sleep through.
I don’t think I’ve ever slept more than 6 or 7 hours in a row. I’ve been sick with the flu and slept maybe 18 or 20 hours out of 24, but always waking up every few hours for some water and an occasional pee.
I think mine was somewhere in the neighborhood of 12-13 hours; likely one of those days after getting home to my parents’ house after finals in college (and the subsequent frantic partying).
I’m pretty sure I tied it a couple times after my sons were born; after some 40+ hours awake (wake up at 6 am on Friday, go to bed at about 10 on Saturday), I went home and crashed while my wife had the babies and all the nursing staff to watch over them. I figured it might well be the last good night of sleep I’d get for a long time, and I was right.
16 hours. Jet lag plus NyQuil gets results.
College study binge, i was up probably 32 or so hours. When I finally crashed, I think I slept about 20 hours. Both the longest I have stayed awake and the longest I have slept.
I guess I’ve never been sick enough to sleep as long as some of you folks have. May you never be that sick again.
12 hours is my record, I think. I took a little weekend trip to another town on my own and stayed at a nice old hotel there near the beach. Woke up the next day from the best sleep of my life with just enough time to dress, casually get my stuff together and split before check-out time.
That was in the days before my bladder began making certain demands on me in the middle of the night. But, I have to say, I’ve gotten pretty good at going right back to sleep as soon as my head hits the pillow.
27 hours - returned from a week long school trip with 14 hours of sleep over the whole week. I did not get up to pee and did not respond when someone tried to wake we. After 27 hours I woke up and resumed life.
I think I got at least 7 hours a couple of months ago.