Tophane means "canon foundry", the district is named after this building. The foundry was established by Fatih Mehmet, and enlarged under Beyazit II. Even the one that followed it, from Süleyman the Great's time, has disappeared, this one is from Selim III, 1803. It has finally become an exhibition hall. A good one. Nice views can be had from the platform in front.

I put it with Museums, and am not certain if it is opened when there is no exhibition.