We used the "Mother of All Bombs" in Afghanistan once..its like the Vietnam era daisy cutters on roids
Pretty nice for clearing an area for a landing strip of vegetation/insurgents
The British 22,000 pound "Grand Slam" actual was one of the first pentrating bombs. Used in 1945 against the Bielefeld railway viaduct in Germany, which was not destroyed by the thousands of pounds of bombs dropped by B17's, the Grand Slam penetrated the ground next to the said viaducts, created small seismic activity, and collapsed them. It was known as "the earthquake bomb." Pretty cool stuff, all this weaponry.
This new German self propelled gun is pretty impressive. The PzH 2000, or Panzerhaubitze can fire 10 to 13 rounds per minute with its autoloading mechanism

Thats more quickly than soldiers could fire aimed shots with bolt action rifles in WWI!
Leave it to the Germans