I know they're mountains...I'm teasing EP about it.
And since it's the quickest route to the Rhine, it was one of the two obvious ways of invading Germany. They deployed Davey Crockett and the W54 warhead....
One of the smallest nuclear weapons ever wielded, the Davy Crockett was developed in the late 1950s for use against Soviet troops in West Germany. Small teams of the Atomic Battle Group (Charged with operating the device) would be stationed every few kilometers to guard against Soviet attack, using the power of their nuclear artillery shells to kill or incapacitate advancing troop formations and irradiate the area so that it was uninhabitable for up to 48 hours, long enough to mobilize NATO-Forces.
U.S. officials view a Davy Crocket casing.The M-388 round used a version of the W54 warhead, a very small sub-kiloton fission device. The Mk-54 weighed about 51 lb (23 kg), with a selectable yield of 10 or 20 tons (very close to the minimum practical size and yield for a fission warhead). The complete round weighed 76 lb (34.5 kg). It was 31 in. (78.7 cm) long with a diameter of 11 in. (28 cm) at its widest point; a subcaliber piston at the back of the shell was actually inserted into the launcher's barrel for firing.
The Davy Crockett could be launched from either of two launchers: the 4-inch (120 mm) M28, with a range of about 1.25 mi (2 km), or the 6-in (155 mm) M29, with a range of 2.5 mi (4 km). Both weapons used the same projectile, and could be mounted on a tripod launcher or carried by truck or armored personnel carrier. They were operated by a three-man crew.
Both recoilless rifles proved to have poor accuracy in testing, so the shell's greatest effect would have been its extreme radiation hazard. Even at a low yield setting, the M388 would produce an almost instantly lethal radiation dosage (in excess of 10,000 rem) within 500 feet (150 m), and a probably fatal dose (around 600 rem) within a quarter mile (400 meters).
http://en.wikipedia.org/wiki/Davy_Crockett_(nuclear_device)
Also, you got a few of these laying around:
Medium Atomic Demolition Munition (MADM) was a tactical nuclear weapon developed by the United States during the Cold War. They were designed to be used as nuclear land mines and for other tactical purposes, with a relatively low explosive yield from a W45 warhead, between 1 and 15 kilotons. Note that this is still very powerful by conventional explosive standards; for example this is slightly more powerful than the bomb that destroyed Hiroshima and more than two to three orders of magnitude larger in explosive power than the largest conventional bomb, the MOAB. Each MADM weighed around 400 lb (181 kg) total. They were produced between 1965 and 1986.
http://en.wikipedia.org/wiki/Medium_Atomic_Demolition_Munition