Moscow is located on the Moskva River, which bends its way through the southern and western parts of the city. Most of the main sites are on the northern bank of the river. The other major waterway is the Yauza River, which flows into the Moskva east of the Kremlin.

Much of Moscow's geography is defined by the numerous 'Ring Roads' that circle the city at various distances from the center. With Red Square and the Kremlin forming the very center, the innermost ring road is the Boulevard Ring, which which runs from the Christ the Saviour Cathedral in south-west central Moscow, to the mouth of the Yauza in south-east central Moscow.
The next ring road is the Garden Ring, which used to be the place of Moscow's outer walls. It derives its name from the fact that landowners near the road in Tsarist times were obligated to maintain gardens to make the road attractive. In Soviet times the road was widened.
The recently constructed Third Ring is not much use for tourists but is a heavily used motorway which absorbs a bit of Moscow's traffic. The outer edge of Moscow is largely defined by the Moscow Ring Road, a motorway which encircles the entire city (similar to London's M25 and Paris' Peripherique). Finally, a Fourth Ring is due to be built between the Third Ring and the Moscow Ring Road in the next years.