Duntulm Castle on Skye in ruins now but the views are beautiful
http://www.aboutaberdeen.com/duntulm_castle.php
The RSPB Visitors Centre at Aros on Skye, a wonderful place to visit where you can see live TV showing the nests of White Tailed Eagles, the Visitor Centre film theatre [if still there] is highly recommended too
http://www.rspb.org.uk/datewithnature/146927-aros-whitetailed-eagles
The Commando Memorial at Spean Bridge, Ben Nevis http://en.wikipedia.org/wiki/Commando_Memorial