At one time, there were two paper mills in Polton adding their belching smoke to the total of four mill chimneys along the length of the Lasswade valley. Their buildings are now demolished, the grounds of one is now a wildlife site - Springfield Mill Nature Reserve. The weir which provided the head of water to power that mill can be seen - and heard - looking down from the top of the Hewan Bank near the Maiden Castle - but with great care, as the Bank is a Site of Special Scientific Interest for the geology of its glacial deposits and is subject to regular erosion and landslides. The footpaths in this area have been upgraded to avoid damage to the Bank.
Nearby is Mavisbank House, once one of Scotland's finest buildings. Designed by William Adam for Sir John Clerk as a summer residence and at a convenient travelling distance from Edinburgh while he was working there, it sits on the wooded slope of the Esk valley surrounded by landscaped parklands. From the late 19th century until 1951 it was used as a hospital for the mentally ill but later, back in private ownership, it was gutted by fire in 1973. The house is now a sad ruin but remnants of the 'Designed Landscape' still remain and there is greater public interest in their future after the recent 'Restoration' TV series. The Mavisbank Trust is working hard on this.
On the opposite bank of the river is De Quincey Cottage named after the eccentric writer Thomas De Quincey who made his home there from 1840 until 1859. The single track skewed steel bridge which took travellers and mill workers over the river for decades was replaced by a new concrete bridge in 2006.
The Esk Valley Trust have produced a leaflet showing walking routes between Lasswade to Polton and Loanhead.