Ukraine Why are Russian forces fixated on Bakhmut

Russian forces are concentrating their efforts on the seemingly strategically unimportant town of Bakhmut. But why is this? Defence expert and former British Army officer Lieutenant Colonel (Retired) Glen Grant has spoken to news media. Bakhmut was founded as a salt mining town, the mines there aren't open pit, the salt is 300m below the surface and there are hundreds of miles of big tunnels you can drive vehicles in. The USSR used to store millions of tons of ammunition in Ukraine's salt mines, is it possible they want the area as a protected storage for logistics? Put the phrase "Soledar salt mines" in an image search to see just how big the tunnels are and 300m below the surface is a very safe place, no HIMARS can touch you.