Like the rest of the Gangetic Plains, Delhi is as flat as a pancake. The only geographical features of any significance are the river Yamuna, which flows down the eastern side of the city, and the Aravalli Hills, which form a wide but low arc across the west. On the west bank is the crowded and congested Old (Central) Delhi and, to the south, the broad, tree-lined avenues of New Delhi, built by the British to rule their empire. The rest is an endless low-rise sprawl of suburbia and slums, with southern Delhi (nearer to New Delhi) generally somewhat wealthier and the western reaches rather poorer. Indeed, on a broad scale Delhi is not difficult to navigate. The Outer Ring Road, and Ring Road, offer simple connections between districts. In South Delhi, most of the major districts lie on either the inner or outer ring roads. Traveling west on the Ring Road from Nizammudin, the following colonies lie in the following order, Friends Colony, Lajpat Nagar, Defence Colony, South Extention, INA, Safdarjung, Bikhaji Kama Place, RK Puram, Chankyapuri, Dhaula Kuan. And on the outer Ring Road, traveling west from Okhla, the following colonies lie in the following order,Nehru Place, Kalkaji, GK2, GK1, CR Park, PanchShil Park, Hauz Khas Enclave, Safdarjung Enclave, Munirka, Vasant Vihar. The only major areas that lie in between the Ring Roads as opposed to adjacent to them are are Anand Niketan, Hauz Khas Village, Green Park. However, these areas are easily accessible from Shanti Path, Aurobindo Marg, and Khel Gaon Marg respectively. Inside the colonies it is another issue, often akin to mazes, finding your way around the inside of any colony other than Vasant Vihar or Chanakyapuri is not for the faint hearted. Delhi's climate is, sad to say, infamously bad, combining the scorching aridity of Rajasthan's deserts with the frigid cold of the Himalayas. From April to October, temperatures are scorchingly hot (over 40 deg C is common), and the monsoon rains deluge the city in July and August. With every air-conditioner running at full blast, the city's creaky infrastructure is often stretched beyond the breaking point, with power and water outages common. In winter, especially December and January, temperatures can dip to near-zero and the city is blanketed in thick fog, causing numerous flight cancellations. The shoulder seasons (Feb-Apr and Sep-Nov) are comparatively pleasant, with temperatures in the 20-30 deg C range, but short.