A pretty astonishing edifice in its own right, the Palais Longchamp also has a excellent range of family attractions clustered around it.
Set on a hill, it's surrounded by extensive grounds with ancient trees, fine views across Marseille (Notre Dame de la Garde can be glimpsed in the distance), plentiful places to picnic and several children's play areas with swings, roundabouts, etc.
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Behind the Palais and to the left, the Observatory and Planetarium offers son et lumière shows, temporary exhibitions, currently one about the influence of planets on the tides. The Planetarium also houses Foucault's enormous historic telescope - once the largest in the world - dating from 1864.
It's recommended for children over seven; there are special shows at certain times for younger children too. Website for the full Planetarium programme and opening hours (in French only).
The Palais Longchamp has plenty of spaces for children to let off steam: apart from the large garden in front of the monument, there are three big, interconnected parks behind it, dotted with several playgrounds.
These are a magnet on a hot summer's day - throughout the year, in fact - for families living in this part of town. Pictured: one of these play areas. Note the aqueduct in the background.
They include oriental pavilions for giraffes and elephants, cages ornamented with Turkish tiles and seal dens decorated with rocaille, or rock-work.
The zoo closed down in 1987 and the ornate enclosures became listed buildings. But in 2013 it was briefly given a new lease of life, with a temporary "Funny Zoo" of brightly coloured fibreglass creatures, known as Z'Animaux.
Housed in the right-hand one of the Palais' two huge wings (as you face towards the Palais), the Natural History Museum has four sections, devoted to prehistory and evolution, osteology (that's skeletons and skulls to you), the flora and fauna of Provence and a "safari room" featuring over 300 exotic (stuffed) animals. It also hosts temporary exhibitions.
If your kids speak French, you might enquire about the regular "nocturnal safaris," evenings when groups are guided around by a storyteller. Note that much of the signage and explanations is in French only.
The museum is open from 10am to 5pm and admission is free on Sunday mornings. Closed Mondays and public holidays. Website for the Museum d'Histoire Naturelle (in French only).
Older children might be interested in the Grobet-Labadié Museum, pictured, which is just across the road from the entrance to the Palais grounds.
This is a graceful old 19th century house that recreates the intimate and comfortable atmosphere of a wealthy, cultured merchant's residence, with tapestries, wood-carvings, musical instruments, chinaware and paintings and even a sedan chair.
Closed Mondays and public holidays. There's a small admission charge. Website for the Grobet-Labadié Museum (in French only).
Where: Palais Longchamp, Boulevard du Jardin Zoologique, 13004 Marseille
How to get there: Metro (line 1, stop Cinq Avenues Longchamp), tram line 2 or bus 81.