Sydney is the main port on Cape Breton Island, in Nova Scotia.

Sydney is on the east bank of the Sydney River where it discharges into South Arm of Sydney Harbour. Elevation ranges from sea level to 66 m (217 ft) above sea level.

The majority of properties within the former city limits have been impacted by development and an extensive urban road network. The central business district is located on a peninsula extending into South Arm formed by Sydney River on the west side and Muggah Creek on the east side. The largest park within the former city limits is Open Hearth Park.

Distinctive neighborhoods include Whitney Pier in the northeast end next to the former steel plant site, Ashby in the east end, Hardwood Hill in the south end and the "North End" located on the peninsula which contains the Holy Angels convent and the Sydney Garrison known as Victoria Park, headquarters of the Cape Breton Highlanders reserve infantry regiment. The former city completely encircles the Membertou First Nation (First Nations Reserve 28A and 28B).

Climate

Sydney experiences a cool summer and windy, wet and stormy winter, version of a humid continental climate (Köppen Dfb) that is significantly moderated by the community's proximity to the Atlantic Ocean. The highest temperature ever recorded in Sydney was 36.7 °C (98 °F) on 18 August 1935. The lowest temperature ever recorded was −31.7 °C (−25 °F) on 31 January 1873, 29 January 1877 and 15 February 1916.

Due to the relatively strong influence from large bodies of water, Sydney experiences strong seasonal lag, meaning February is the year's coldest month on average, and August is the year's warmest month on average. By contrast, in most continental climates in the Northern Hemisphere, January is the coldest month, July the warmest.

In other respects, too, Sydney's climate varies significantly from that of other areas with humid continental climates. The most significant variations are that Sydney experiences unusually cool summers, and relatively windy, wet and stormy winters, relative to other humid-continental areas such as in the interior of North America. Annual temperatures are instead rather similar to areas around the Baltic Sea in north-eastern Europe at much higher latitudes, although Sydney's seasonal lag is stronger. Although Sydney has some maritime influence, similar latitudes on the other side of the Atlantic have significantly milder climates in all seasons except summer. Sydney is in the direct path of fall and winter storms (in the U.S., called nor'easters) migrating from the U.S. Northeastern and New England states; these storms can attain tremendous intensity by the time they approach Sydney, with high winds, heavy snow, ice and/or rain events common, primarily from October to March. Summer thunderstorms are rare in Sydney because nearby bodies of cool water sharply inhibit the combination of heat and humidity that fuels summer-season thunderstorms elsewhere (for example, the United States' central and southeastern states, and east-central and northern China).

While occasional thunderstorms and other rains can occur in summer, June through August are Sydney's driest months on average. Sydney's average annual precipitation cycle reflects these realities; the year's driest month, on average, is July; its wettest month, on average, is December. Average annual precipitation in Sydney is over 1500mm, virtually the highest found anywhere in Canada outside coastal British Columbia. Snowfall is heavy, averaging nearly 300 cm per winter season. However, winter-season storms are variable and can bring changing precipitation types, commonly from ice/snow to rain and possibly back to ice/snow. As such, actual snow accumulation is variable. A winter storm can bring accumulating snow, followed by heavy rain, then a brief return to snow or ice, resulting in no or minimal additional snow accumulation. Overall, Sydney's climate is moderately cold and strikingly variable, wet, stormy and windy from fall to early spring (October to March), and more stable and drier in summer (June to August).