Free historic Scotland

Historic Scotland's free weekend is coming up, where visitors can enjoy a number of our historical sites which normally cost for entry for free, including Edinburgh Castle on April 21st and 22nd. Looking on the HS site which has a list by region of attractions is a nice reminder of some of the history which is still physically with us (a lot which I haven't seen yet) literally covering not mere centuries but millennia, from Maeshow and Skara Brae to the dramatic remains of Tantallon Castle perched on the rugged, rocky cliffs looking out over the Forth (very Castle Dracula in the right lighting and weather). The RH site has details and individual entries even give OS map references and travel guides including information on going there using the National Cycle Network. Why do I have the troubling worry I will forget about this and remember on the following Monday and realise there was something I meant to do...