The Wellington or Waterloo Monument stands on the summit of Penielheugh. It is a stone Doric column 150 feet high, built by the 6th Marquis and his tenantry to commemorate the Duke of Wellington's victory over Napoleon.

This dramatic local landmark represents the second attempt on the site by the 6th Marquis. The first, a pyramid built in 1815 to the design of William Burn fell down ‘with a tremendous crash’ only a year after construction. The existing monument in the form of a ‘Triumphal Column’ was designed by Archibald Elliot and began in 1817. It took 10 years to build, the stone being quarried locally.