[Dosa26]

Actually, in the case of Seoul, they don't need a nuke. They have 250,000 artillery tubes and missile rails pointed at it within range.

It's not a quarter million, but it is enough to reduce Soul to Grozney in hours.

[AFPhys]

I believe it has been well established that NK can pummel Seoul with in excess of 300,000 artillery rounds within three hours. For example, from:

http://www.cuttingedge.org/news_updates/nz1138.htm

Global Security, Inc.

August 30, 2003

North Korea has about 500 long-range artillery tubes within range of Seoul, double the levels of a the mid-1990s. Seoul is within range of the 170mm Koksan gun and two hundred 240mm multiple-rocket launchers. The proximity of these long-range systems to the Demilitarized Zone threatens all of Seoul with devastating attacks. Most of the rest of North Korea's artillery pieces are old and have limited range. North Korea fields an artillery force of over 12,000 self-propelled and towed weapon systems. Without moving any artillery pieces, the North could sustain up to 500,000 rounds an hour against Combined Forces Command defenses for several hours.