Calton Hill was purchased by Edinburgh's town council in 1724 and established as one of the nations first public parks. It's geologic origins are volcanic and glacier carved from the ice ages. It provides an incredible view of the surroundings and was a spot where quite a number of monuments were erected for various purposes. The imposing one to the left is in honor of Dugald Stewart, an Edinburgh born writer and philosopher.
The National Monument commemorates Scottish soliers lost in the Napoleonic Wars. It is based on the design of the Acropolis in Athens and was part of the architectural renaissance which gave Edinburgh the nickname, the Athens of the North. Does it look like it fell into ruins? No, they ran out of funding and stopped.
The castle like building is the City Observatory. I can't find a reference for the obelisk. I'll look later.
The hill path is a lovely walk. Here we are approaching the Nelson Monument, in honor of Admiral Horatio Nelson, who died leading his troops in the Battle of Trafalgar. (We'll see him again in London.) This monument is designed after an upended telescope. You can see the resmblance better in the next picture. It also serves--or served--a practial purpose. A large white ball on the side facing the Firth of Forth is raised each day and dropped precisely at 1:00 p.m. This served as a time signal for the ships in the firth to set their instruments by. Of course, fog and rain prevent that from being as practical as it might seem, so an additional signal of a cannon shot from the castle was added. That is still done daily except Sunday as a tradition, though modern instruments make it unnecessary for navigation purposes.
The view from Calton Hill includes Edinburgh Castle in the distance, The Walter Scott Monument, St. Giles Cathedral, the National Gallery of Scotland, and the Royal Scottish Academy. In the opposite direction you can see Arthur's Seat, another volcanic mound--and a link to Scottish connections to King Arthur.