Uneven Surface. Where the surface layers are made of limestone rocks, the water reaches very deep through the holes existing in the surface. The underlying rocks develop numerous holes by the solution of rocks. When these holes cannot withstand the load of the upper layers, the latter collapses on to the holes. This makes the upper surface uneven. The subsidence of the surface due to solution is called Solution subsidence.
Laples of Karren or Clints. Solution process is accelerated when water falls over the rocks. Due to solution of the rock, long furrows are formed which have vertical walls. Such features, which are grooved and fluted, are usually found parallel to each other. They are known as Karren. In Britain, the karrans are called clint but are known as Lapies in France.
Caverns / caves. Many caverns / caves are formed by the solution action of underground water which slowly hollows the interior of a limestone feature. The hollow part of such features under the ceiling gives them the shape of a cave. These caves or caverns are found small as well as large. Smaller caverns / caves develop into larger caverns / caves.
Natural Bridge. When a cavern collapses, a part of it remains intact and appears as a Natural Bridge.
Sink Holes. Sink holes are formed in two ways. When the roof of a cavern collapses, sink holes are formed. The second way in which sink holes are formed is due to solution. Water makes holes at the joints of rocks by solution action. These holes on development into bigger ones, conduct water into caverns.
There are hundreds and thousands of holes in limestone areas. These holes can be recognized by their funnel-shaped shapes with vertical walls. Their diameters vary from a metre to thousands of meters. These holes are known as Avens in France, Doline in Dinaric areas, Swallow Holes in U.K. and Sink Holes in America.
Sometimes, these sink holes are closed by the debris from the adjoining areas. Such holes develop into lakes known as Karst Lakes. Alachua Lake of the Florida is good example of such lakes.
Locals hypothesize that the legacy of Italian blood and culture in Cologne, colonized by the Romans more than 1500 years ago, makes the people more jovial and lighthearted. Cologne is the largest city on the Rhine.
Kolsch is not only the dialect spoken here but, also the name of their own top-fermented beer. There are more than 4,000 pubs, restaurant's and brewery taverns in Cologne.
Unlike many of the world's large cities, Cologne, with a population of over a million, gets better every day, there are more things to do and see, more new and innovative buildings... more
Travel is an opportunity to learn, whether geography, languages, history or other subjects.
Cologne is situated on the beautiful Rhine River.