The principal mountains are the Arakan Yomas, which send out spurs and sub-spurs almost to the sea-coast.
To the east of the Arakan division, and separated from it by the Arakan Yomas, lies the main body of Burma in the basin of the Irrawaddy.
The second tract is that known as the dry zone of Burma, and includes thewhole of the lowlands lying between the Arakan Yomas and the western fringe of the Southern Shan States.
This tract consists mostly of undulating lowlands, but it is broken towards the south by the Pegu Yomas, a considerable range of hills which divides the two remaining tracts of the Irrawaddy basin.
On the west, between the Pegu and the Arakan Yomas, stretches the Irrawaddy delta, a vast expanse of level plain 12,000 sq.
To the east lies a tract of country which, though geographically a part of the Irrawaddy basin, is cut off from it by the Yomas, and forms a separate system draining into the Sittang river.
The Arakan Yomas starting from Cape Negrais extend northwards more or less parallel with the coast till they join the Chin and Naga hills.
The highest peak of the Arakan Yomas, Liklang, rises nearly io,000 ft.
Compared with these ranges the Pegu Yomas assume the proportions of mere hills.
South of Thayetmyo, where arms of the Arakan Yomas approach the river and almost meet that spur of the Pegu Yomas which formed till 1886 the northern boundary of British Burma, the valley of the Irrawaddy opens out again, and at Yegin Mingyi near Myanaung the influence of the tide is first felt, and the delta may be said to begin.
East of the Rangoon river and still within the deltaic area, though cut off from the main delta by the southern end of the Pegu Yomas, lies the mouth of the Sittang.
The greatest elevation of the Arakan Yomas in Henzada, attained in the latitude of Myan-aung, is 4003 ft.
Three ' mountain ranges traverse the district - the Pegu Yomas, the Karen, and the Nat-taung or- "Great Watershed" - all of which have a north and south direction, and are covered for the most part with dense forest.
The Pegu Yomas have a general elevation of from Boo to 1200 ft., while the central range averages from 2000 to 3 000 ft.
On the west is the Arakan Yoma range, and on the east the Pegu Yomas; and the face of the country, where it does not rise into mountains, is everywhere broken ty low ranges of hills, many of which are barren and destitute of all vegetation.
The greater part of the district is wooded, and the Yomas east and west are covered with forests, now mostly preserved.