One of the must haves for us... a big bed...though this coach came with twins,and cushions to mak a over sized king... one nap in the coach and it's done..so what I did was, take all the cushions out, cut a piece of plywood , filled the hole... the bought a king size mattress... it fits right in there.. it's 75 x84 I think,... I'm bush high...5'9"...wife 5'2'' so we are able to sleep north south.. on the 75'' way,.. but for you tree top lovers,6' and above, if you sleep the other way it's about 88''.. cool thing is standard king sheets fit, so no over priced custom size sheets