Inphysical structure the Republic of Yemen can be  divided into fiveregions:  

       1.The Mountainous Region.

       2.The Plateau Region.

       3.The Coastal Region.

       4.The Ruba Al-Khali Region.

       5.The Yemeni Isles Group.

(())Firstly:

TheMountainous Region of Yemen were created due to the African splitwhich was occurred by the drift appart and hence formed the RedSea and the Gulf of Aden … i heights is gradually rising from1000-36000 m. as the heights acme of the mount of (Na Shuaib)reaches (3666)m., which is the heights acme in the ArabianPeninsula and the Sham.                                 Thedistribution line of water is in these mountains from where waterruns easterly, westerly, northemly, southemly, areas. And themain of these wadies are:                                      One.  The Wadies run water to the Red Sea are: Wady Harad, Wady Mour,Wady Surdud, Wady Rama, Wady Siham, Wady Zabid, Wady Mawza andWady Rasiyn.                                     Two. The wadies pouring in the Gulf of Aden and the Arabian Sea are:Wady Tuban, Wady Bana, Wady Ahur and Wady Hadramaut.                 Three. The wadies sloping to the east: Wady Khabb, Wady Al-Jawf andWadyAdhana.      Four. The wadies sloping to the north and north east are:

Wady Harib,Wady Markha, Wady Jardan, Wady Aiot Al-Sayar, Wady Ramah and WaydShuaith.The mountain chain in its long extension is permeated byplain lowlands and beds forming vast areas between the mountainsforming blockades for “syol” rushing floods and dams forfeeding through channels to irrigate vast agricultural areas, themain of these lowlands are:   Sa’da lowland, Al-Bon lowland, the bed of Sana’a, Jahran lowland, Al-Haql lowland (between Ibb&Dhamar, Al-Hoban lowland (in Taiz),Wady Hadramaut and Wady Baihan in Shabwa, Haraz lowland (Hadramaut),Aiwa lowland (Hadramaut), and Shuaith lowland (in Al-Mahara).

(())Secondary:

    The Plateau Region is situated in the east and north of the mountainous heights and parallel to it but it is expanded more towards Ar-Ruba Al-Khali, and gradually begins to descend.  Its maximum height is 1000m. and it includes Sa’da region, Al-Jawf Provinec, Shabwa Province, Hadramaut and Al-Mahara province.

It is formed from hill rocks and water slopes to if from the mountainous areas, and its edges are interweaved to the Ruba Al-Khali from the north side.

 (())Thirdly:

    The Coastal Region includes the plain coast of the Red Sea, the Gulf of Aden and the Arabian Sea, it is linked to each other forming a coastal strip and extends strip and extends from the borders of Oman south west towards Bab Al-Mandan and turn direction to the Saudi b orders.  Its length is nearly 2000 km.  The width of this area varies between 30-60 km

(())Fourthly:

    Al-Ruba Al-Khali Region, it is part of the desert regions of Yemen which is permeated by some land plants specially in its edges intercepted with the plateau region through the seasonal wadies and sand roots.

Name of the Ruba Al-Khali are numerious through the historical periods of Yemen, thus we find it named : The Quivering Sea, the Clear Sea, the Great Yemeni Desert and the Curvilineal Desert etc., and whenever we go far inside the Ruba Al-Khali the plant life and waters become rare and the moveable and dunes increase, and which vanishes the features and traces.

 (())Fifthly:

     The Yemen Isles Group, are scattered in the sea zone of Yemen in the Red Sea and in the Arabian Sea and has its own climate, weather and environment as it has its natural reliefs and formations, most of the Islands concentrate in the Red sea distributed along the Yemeni coast forming an archipelago.  The main and large one is Kamarah which is inhabited with people and with some land rare animals.  And to the north it there is the Island of Baklan.  Al-Tair and Al-Fashit, and to the south of Kamaran Hanesh Al-Kabeer and Hanesh Al-Saquir islands.  The Island of Mayooon “Terim” divides the strait of Bab Al-Mandab into two parts. 

The Yemeni islands in the Arabian sea are found near each other and the well known one is Socotra Island land of Andem and Dam Al-Akhwan tress which produces olibanum medicinals, incenses and dyes some of which are used for decoration also found in this island are some of African origin.

Near Socotra island also there are a group of small isles the main of which is the island of Abdel Kuri, and islands of the two brothers (Samha & Darsa).