National Museum of Scotland
In central Edinburgh at the corner of Chambers Street and George IV Bridge. It appears to be built from large blocks of the traditional Leith sandstone of Edinburgh, but this is an illusion. The blocks are actually facing material bolted on to the underlying supporting structure. That's why if you look closely you see no cement between the blocks, just free space. All those stone blocks are hanging freely and independently in space.
The architecture is highly symbolic. For example, the odd protrusion on the far right is the slightly open drawer of a filing cabinet.