When I was looking into something for exactly that use (before I decided to go full suspension) I was looking for a Specialized Chisel hardtail.
Another one worth considering, in that case, is the Chisel’s trail bike cousin, the Fuse. A little bit slacker, adjustable dropouts, and 120-130mm on the front. I’ve got one (second hand) and hopefully will be using it with some friends this summer on a trip from Austria to the Italian Dolomites.
The only downer I’ve found with it is that the seat tube bottle bosses are rivnuts, which limits the length of dropper I can use to 180m on a medium. This is a consideration if you’re a shortarse like wot I am, possibly less of a problem on larger frames for larger people – not sure. Stack is possibly quite low for larger peeps, but that’s easily rectified with taller bars.
If sliding dropouts are important, note there are two versions of the frame – the spendier ones have sliders. They’re one of the more dependable sliding dropout designs I’ve used – really nicely thought out.
I can’t help thinking that if anyone other than Specialized had come out with this frame, people would be raving about it.