You can get to Darling Harbour, a former dockside harbour that has been transformed into a major tourist spot,

Circular Quay, the hub of ferry transport on Sydney Harbour, and The Rocks, the founding point for settlement in Australia and now a vibrant tourist region.

There are six stations that form the main City Circle underground railway.
They are (running clockwise): Central Railway Station, Townhall, Wynyard, Circular Quay, St James and Museum.

Eastern Suburb Extension

Just over a decade ago, a new rail link was built linking the CBD - financial district to Kings Cross and Sydney's eastern suburbs. The link terminates at Bondi Junction, which is several kilometres short of Bondi Beach.

Suburban rail network

Sydney has a vast suburban rail network and frequent rail services, making trains much quicker than buses.
The underground city circle comprises seven city centre stations. Lines radiate from the city Circle, but the rail net work does not extend to the northern or southern beaches, Balmain or Glebe.

All suburban trains stop at central station and usually one or more of the other city circle stations as well. (A ticket to the city will take you to any station on the city circle.

Trains run from around 5am to midnight.
After 9am on weekdays and at any time on weekends.

you can buy an off peak return ticket for not much more than a standard one way fare.

A trip anywhere on the city Circle or to a nearby suburb costs:
$1.80 single,
$2 off peak return
$3.20 day return.

A city Hopper costs $5.40 and gives you a day of unlimited rides in the central area after 9am on weekdays and any time on weekends.
You can go as far north as North Sydney and as far south as Kings Cross, on this ticket.

Staffed ticket booths are supplemented by automatic ticket machines at busy stations, it's cheaper to buy a ticket to your ultimate destination - however don't leave an intermediary station en route or your ticket will be invalid.

For rail information ask at any station or drop by the rail information booth near the ferry ticket office at Circular Quay.

City Rail

Single = One way journey between two nominated stations on the day the ticket is purchased. Return journey between two nominated stations on the day the ticket is purchased.

Off-Peak Return = Return journey between two nominated stations commencing after 9am on weekdays (earlier in some outlying areas) and all day on weekends and public holidays. You can save up to 45% off the return fare.

CityHopper = Unlimited rail journeys after 9am weekdays and all day any weekend or public holiday between the City Circle stations Central, Town Hall, Museum, St James, Circular Quay, Wynyard, Martin Place as well as-Kings Cross and across the Harbour to Milsons Point and North Sydney.

Pensioner Excursion = If you have a Pensioner Concession Card or Seniors Card, you can travel on a Pensioner Excursion ticket.
This gives you unlimited all day travel in the area you select, as well as on Sydney Buses and Sydney Ferries services.

Note All the above tickets are available at ticket vending machines and CityRail ticket offices.