The Northern Beaches of Sydney refers to a suburban district located in the north east of the city, as well as a stretch of famous beaches extending northwards from Sydney Harbour and North Head at Manly to Barrenjoey Point and Broken Bay, fronting the Pacific Ocean.
In general, the suburbs that fall within the Manly, Warringah and Pittwater local government areas are considered the "Northern Beaches".
Manly - The major tourist centre, destination of the famous Manly ferry.
Located on the hilly areas and plateaux immediately behind the beach suburbs, are the so-called "forest suburbs", so named because of the large tracts of natural bush land which feature in this area. These include:
Frenchs Forest - The major centre of the forest area.
Terrey Hills - A quier suburb with a laid back community
Beacon Hill - The highest point in the area.
The Northern Beaches is surrounded on all sides by either water or forest areas, causing some locals to call the area "the Peninsula".
Northern Beaches is a "family-orientated" area and topless bathing is generally not the norm; it still occurs in Manly, but is less common than at the beaches on the other side of the Harbour such as Bondi, Tamarama, etc.
Manly Beach is the most popular destination for tourists and visitors, with a range of attractions and activities aimed at the day tripper and holiday maker. In reality, there is so much more the Northern Beaches has to offer than this tiny southern portion and less tourists and crowds will make it more enjoyable.
There are no rail services to the Northern Beaches.
The Northern Beaches are serviced by a regular ferry service between Manly and Circular Quay (Sydney Centre). These services are operated by Sydney Ferries .
The Palm Beach Ferry  operates a ferry service between Palm Beach and Ettalong (on the Central Coast).
Regular State Transit Authority  buses run from the city to Palm Beach, and from Manly to neighbouring suburbs. Suburbs in the Forest area are serviced by a private bus company, Forest Coachlines.
There are only three ways to get to the Northern Beaches by car. The first route is the Spit Bridge from Mosman (Military Road/Spit Road). The second route is across the Roseville Bridge (Warringah Road), from Chatswood. The third route is via Mona Vale Road, which comes from Pymble/St Ives.
Running north to south along the beaches, the main road artery is Pittwater Road/Barrenjoey Road. Another major road, connecting the north and south through the Forest area, is Wakehurst Parkway, which offers a beautiful drive through natural bushland.
The spit bridge is a gridlock point for traffic. Many commuters try to use the T3 (transit 3) lanes, which are for carpooling. Northern beaches carpools are also available .
With the exception of the hassle of parking at the beaches on summer weekends, a car is a flexible and easy way to travel around the areas.
There are a couple of specialised local service ferries around the northern beaches.
Local Pittwater services operate between Palm Beach and Great Mackerel Beach. The Church Point Ferry company  provides services on Pittwater between Church Point and Scotland Island.
Manly and Sydney/Palm Beach have many things to see. Read about them in the articles on those areas. Outside of those centres:
The Northern Beaches is famous for its beaches, each with its own distinctive character. Northern Beaches buses ply the route between Manly and Palm Beach, passing all of the ocean beach suburbs along the route.
Sydney/Manly. The Harbour beach and long Ocean Beach, connected by the Corso, with shops, cafes, restaurants, and surrounded by many other attractions.
South Curl Curl. A larger beach. Has a 50m rock formed ocean swimming pool. Ocean currents in the beach can be strong, and especially important to swim between the flags. Public transport access by bus. 
North Curl Curl. A popular beach, with nice cappuccinos served right on the sand. Get there early on secure your space on the sand, and a parking spot on summer weekends. Nice cliffs providing more entertainment for children, with a small caves in the cliffs to play in. Parking difficult, but usually possible. Public transport access by bus 
Pittwater, in the far north of the Northern Beaches, is a waterway with a number of attractive beaches and pleasant scenery.
Close to the Beach
The Baha'i temple located on the top of a hill on Mona Vale Road, is highly visible from many parts of the Northern Beaches.
A high point is Beacon Hill and a lookout offers views across large parts of the Northern Beaches and as far as the CBD of Sydney.
Manly has a range of beachfront and harbourfont activities and beaches, and is the premier tourist destination.
Sydney/Palm Beach and Barrenjoey lighthouse are worth visiting at the Northern tip of the area.
Garigal National Park surrounds the area to the West, with many walks and picnic areas.
There are cinemas in Manly, Brookvale, Collaroy, Warriewood and Avalon.
Rugby League. The major sporting team of the area is the Manly-Warringah Sea Eagles. Manly plays 12 home games each season (March to September) at Brookvale Oval, which is on Pittwater Road near Warringah Mall. There is seating both in covered grandstands and on the grass in the area known as the hill. Manly Sea Eagles website 
Manly-Warringah Sea Eagles Football Club - , Pittwater Road, Brookvale
Cricket. Manly also has a grade cricket side which plays at an oval in Manly itself during the summer season. Grade cricket is essentially a feeder competition for the Pura Cup competition (still regularly referred to as the Sheffield Shield), and top Australian players rarely play at grade level.
Rugby Union. The Northern Beaches boast two main rugby union sides: Manly , based in Manly itself, and Warringah (affectionately known as 'the Rats'), based in Narrabeen
Most Northern Beaches suburbs have small shopping villages oriented towards locals and their needs.
Warringah Mall, located at Brookvale, and one of Sydney's largest shopping monstrosities, with most of the major retail outlets. It is also unique in Sydney as an "indoor/outdoor" shopping centre, reflecting the outdoors lifestyle of the Northern Beaches.
Warriewood Square, located in the Warriewood Valley (much more dull and tacky).
Dee Why has a major strip of shops, while Manly caters mainly for tourist and leisure shoppers. Harbord (Freshwater) has some quiet, but an interesting group of shops where you can buy localised souvenirs such as stickers and beach gear.
Forestway Shopping Centre offers a popular suburban shopping amenity.
There are many restaurants on the Northern Beaches, generally taking advantage of the beachside surrounds.
Manly has many restaurants of all types and price ranges, reflecting the tourist nature of the area.
Dee Why has a number of good restaurants, particularly along the beachfront. The major shopping areas in most of the beachside suburbs offer a good range of cuisines and quality.
Many of the beaches have kiosks operated by the surf clubs but they are limited to sausage rolls, meat pies, chiko rolls, coffees and cold drinks.
Fish and chip shops are everywhere here and an enjoyable evening can be had eating them on the benches in the parks and beaches watching over the ocean.
There are many public hotels on the Northern Beaches. Sydney/Manly has a selection of pubs and nightclubs around the Corso and beach. Many of the forest and beachside suburbs have a pub with its own character - old or newly renovated - quaint or beer barn.
The Arms hotel in Newport.
The tourist centres of Manly and Palm Beach feature a number of accommodation choices from budget to five star. Check their articles for details. Outside of those centres:
Sydney Beachouse YHA, 4 Collaroy Street, Collaroy; tel. 02 9981 1177 fax. 02 9981 1114 (email firstname.lastname@example.org) . Dorm beds $20-$26 per night; double or twin rooms $64 per night; $84 with ensuite.
Checkers Resort & Conference Centre, 331 Mona Vale Road, Terrey Hills, NSW 2084 Australia, ☎ +02 9450 2422 (fax: +02 9450 2778), . Nestled in the bushland surrounds of Terrey Hills, Checkers Resort and Conference Centre offers a stunning location for business or pleasure and a range of accommodations to suit all needs and budget.Best rates on official website start at $99.