Question: Both Gleneig North and the City of Holdfast Bay are suburbs of what South Australian city?

Context paragraphs:
Holdfast Bay: The Holdfast Bay is a small bay in Gulf St Vincent, next to Adelaide, South Australia.  Along its shores lie the City of Holdfast Bay and the popular beach-side suburb of Glenelg.

Grace Benny: Susan Grace Benny, née Anderson, (1872 – 5 November 1944) of Seacliff, South Australia, generally referred to as Grace Benny or S. Grace Benny, was the first woman elected to local government in Australia when she was elected to the Brighton Council (now City of Holdfast Bay) in 1919.

Electoral district of Morphett: Morphett is an electoral district of the House of Assembly in the state of South Australia.  The seat is located 10 kilometres west of the centre of Adelaide, bounded by the Holdfast Bay coastline on the west and Morphett Road to the east.  It is approximately 15.6 square kilometres in size, and is based on the suburb of Glenelg.  It also includes Glenelg North, Glenelg East, Glenelg South, Glengowrie, Morphettville, West Beach and parts of Somerton Park.

Glenunga, South Australia: Glenunga is a small southern suburb of 2,539 people in the South Australian city of Adelaide.  It is located five kilometres southeast of the Adelaide city centre.  The name Glenunga is taken from an Aboriginal language "unga" meaning near and "glen" because of its proximity to Glen Osmond (see Manning's places of South Australia by Geoffrey H. Manning published in 1990).  Bounded on the north by Windsor Road, the east by Portrush Road, the south-west by Glen Osmond Road and the west by Conyngham Street, the leafy suburb forms a rough triangular layout.  It is close by to other Burnside council suburbs of Toorak Gardens and Glenside.

Seacliff Park, South Australia: Seacliff Park is a suburb of Adelaide partly in the City of Marion and the City of Holdfast Bay.  The suburb is adjacent to Brighton and Marino.

Kingston Park, South Australia: Kingston Park is a small beachside suburb, 17 km south of Adelaide.  Kingston Park is within the City of Holdfast Bay and neighbouring suburbs are Marino, Seacliff and Brighton.

Glenelg North, South Australia: Glenelg North is a seaside suburb of Adelaide, South Australia.  It is located in both the City of Holdfast Bay and the City of West Torrens.

Moseley Square, Glenelg: Moseley Square is a public square in the City of Holdfast Bay at Glenelg.  It was named after an early councillor who promoted the building of a railway line to Glenelg.  Located between Jetty Road and Glenelg Beach, the Square is located to important places such as the Town Hall, Glenelg Jetty, and the Stamford Grand Hotel.  It is the terminus of the Glenelg Tram ( the only tram line in Adelaide ) from Adelaide.  It is a site of major events including the Glenelg Jazz Festival and the City to Bay Fun Run.

Glenelg, South Australia: Glenelg is a popular beach-side suburb of the South Australian capital of Adelaide.  Located on the shore of Holdfast Bay in Gulf St Vincent, it has become a popular tourist destination due to its beach and many attractions, home to several hotels and dozens of restaurants.

City of Holdfast Bay: The City of Holdfast Bay is a local government area in the south-western coastal suburbs of Adelaide, South Australia.

Supporting paragraphs: Glenelg North, South Australia City of Holdfast Bay
Answer: Adelaide