Hi,
A few places that I'd recommend.
Haputale... A small busy mountain town, set on a ridge so amazing views all around. Surrounded by mountains , valleys, tea plantations ec.
Ella, a little further south of Haputale,, Ella is a small sleepy village. Again fabulous views every where and great country side to walk through.
Badulla, bigger mountain town, again surrounded by mountains but here they are a bit more less planted and more forested.
All those three are easy to access,, just get the train from Colombo to Kandy. stay a few days to look around there, then get the train again, going south through the hill country. The line passes through Haputale and Ella then finishes at Badulla.
Another area well worth rambling is the Knuckles mountain range, north of Kandy, easily accessed from Matale.
Completely unspoilt area, beautiful scenery.
The first three have pleny of choice of excellent guest houses. Not many in the Knuckles but a few.
Rod.