Grab your water bottle and get out there (perhaps don't take the Metro at rush hour).
1. Take a swim in an outdoor pool
(The Piscine Josephine Baker. Photo: AFP)
There are around 40 public swimming pools in Paris. Obviously, you want to avoid the heated ones, so check out some of the excellent outdoor options.
We recommend the Josephine Baker pool (pictured above) which is actually floating on the River Seine in the 13th arrondissement. And don't miss the Piscine Georges Hermant in the 19th, an Olympic-size swimming pool featuring a massive retractable roof. And then there's the centre aquatique de Neuilly-sur-Seine is great for families and those who want to relax.
And if you are feeling flush then why not head to the historic Molitor pool - the birthplace of the bikini that recently opened after refurbishment.
Cool rating: 8 out of 10. Yes, you're swimming, but so is everyone else.
2. Head to a church
(The interior of the Notre Dame Cathedral. Photo: bvi4092/Flickr)
While it's unlikely you'll ever find the Notre Dame cathedral as empty as in the picture above, it's the perfect place to cool down. In fact, we suggest you head to any stone church in the city for a welcome drop in temperature. And the less well-known the church, the less likely you're going to have to queue up.
Cool rating: 9 out of 10. Churches are often extremely quiet too, a welcome relief in Paris.
3. Find some shade in a public park
Do like the French do - take a book and a bottle of water to one of the city's public parks and sit under a tree. Using a chair for your feet, like in the picture above, is optional. If you don't mind a few tourists, check out the Jardin du Luxembourg on the Left Bank or the caves and waterfalls of Buttes Chaumont in the 19th (though it can be tough to find shade when it's busy).
Or perhaps the best option is head out to the edge of the city whether it's the Bois de Vincennes in the east or Bois de Boulogne in the west. It may cost a few euros to enter the botanical gardens at Vincennes - but it's worth it.
Cool rating: 7 out of ten. Getting there might mean having to take the Metro but the shade will be a relief once there.
4. Eat ice cream on Ile Saint Louis
Cross a bridge to the Ile Saint Louis and find one of the places selling Berthillon ice cream. They're not hard to spot, there's usually a queue out the front. But once the first drop of ice cream touches your tongue, you won't regret the wait. While you're there, wander through the tiny island, and the neighbouring Ile de la Cité which features the Notre Dame Cathedral.
Cool rating: 8 out of 10. The ice cream is cold, but the tourist crowds might be unbearable.
5. Go shopping at the Grands Magasins (yes really)
(Shopping at the Galeries Lafayette. Photo: AFP)
While the queues and the crowds associated with shopping might be your idea of hell, heading to one of the Grands Magasins might actually be the best remedy for the excessive heat. The biggest ones are mostly air conditioned, and it can be quite pleasant strolling through some of your favourite shops in the cool breeze while the rest of the country sizzles.
If the Galeries Lafayette and Printemps are definitely not your thing, you can always do some serious aisle searching in Picard, the frozen food supermarket.
Cool rating: 7 out of 10. You're still shopping, after all.
6. Hire a boat at La Villette
On the north side of the Bassin de la Villette, an artificial lake that connects the Canal de l'Ourcq and the Canal Saint-Martin, you can rent out an electric boat from Marin d'Eau Douce.
The cheapest option is €40 for an hour, but the cost decreases on a per/hour basis the longer you take it. There are roofs on the boat to keep the sun away. And there's normally a decent breeze.
Cool rating: 8 out of 10. It will still be sweltering out there.
7. Play in the Trocadero fountains
How else to celebrate summer than to splash about in a Paris fountain with gay abandon? A particular favourite is the Trocadero fountains by the Eiffel Tower (pictured above).
Cool rating: 8 out of 10. This is only a temporary relief - wear sun cream and get some shade.
8. Watch a movie
(La Géode in the 19th has a massive screen. Photo: Coolmonfrere/Flickr)
This is an easy one, but highly recommended when it's sizzling. Cinemas in France are almost all air conditioned, and an ideal way to escape the sunshine for a while. But be warned - some films that were originally in English may be dubbed into French for the silver screen. Look out for films marked with "VO" (version originale), which means they'll be in the original language with French subtitles.
Cool rating: 10 out of 10. Especially if you catch a good film.
9. Head to the hotels
(Photo: Le Meurice)
Fancy a gin and tonic in a cool setting? Why not head to one of the nicer hotels in the city? Of course, a hotel like Le Meurice near the Louvre musuem will charge you €28 for a single Gin and Tonic (we found that out the hard way), but some might argue it's worth it, especially with their amazing bar (pictured above).
Most would argue that there are cheaper and better options available (and certainly cheaper drinks!).
Cool rating: 9 out of 10. These places are excellent, but pricey. Do not buy a round for your friends.
10. Find a shaded terrace
(Having a drink on a cafe terrace in Montmarte. Photo: AFP)
Why head to a fancy hotel when you can perch yourself in a shady terrace and knock back a citron pressé, (a kind of French lemonade). There are loads of terraces to choose from, but a particular crowd favourite is in Montmartre in the north of Paris. People watching at its finest.
Cool rating: 9 out of 10. Make sure to ask for plenty of ice.
11. Honorable mention - Go deep underground
The catacombs are probably one of the coolest places in the whole city - and as they're underground they're delightfully cold year round. BUT, and this is a big but, waiting times in this season can easily reach three hours, which means unless you arrive very early indeed, "the world's biggest graveyard" might not be the best way to keep cool.
Cool rating: 6 out of 10, due to the wait.