In high summer, Vienna's buildings and city streets radiate concrete heat. The sun beats relentlessly down on bare foreheads, scorching red burn on unsuspecting pale arms. Without a breath of wind, Vienna can become a furnace.Fear not friends, I'm going to take you on a journey to a cool and calming place. A summer Oasis just outside the city.First, you want to jump on the old-fashioned Badner-bahn that begins its trip to Baden directly out the front of the Opera house. Take a deep breath and a long look around you while waiting for the tram. No, really, we have time, just breath in and make a slow panoramic twist to enjoy the very best of Vienna. Here, right in the heart of the city we're surrounded by postcard-perfect sights; architecture, delicious cakes and polite traffic, with St Stephens cathedral spire twinkling in the distance. Which is all very beautiful but isn't going to help cool you off, so don't get too carried away, here comes the tram - the old lady in front of us will race you to an available seat, schnell schnell!See the window seat there? Take it, claim it, own it, it's the best view in the house. You're going to want to see the city shift from Hapsburg grandeur to outer suburban desert. You're heading in direction Baden, with stops in Puckersdorf - which sounds like a fairytale village to me, and is worth taking a mental note to visit. But not today. Today we're escaping this damned heat, through the magic of an efficient public transport system. Look, I know your legs are sticking to the old plastic seats, mine are too, frankly it's a little gross but this is the fastest way to get to our hidden oasis so it will be worth it. Have a look left, if you're quick you can see Karlskirche peeking out at you, ohhhh and coming up on the right is my absolute favourite street of hipster cafe's, the glorious 4th district. It's dotted with lovely outdoor terraces, a bagel spot, vegan burger bar, Vollpension and….no we really must get to this oasis, resist your urge to dive for cake. The tram takes about 20 minutes so you have a bit of time to relax and enjoy people-watching out the windows.Pulling up to SCS, this is our stop - try not to be distracted by the lure of IKEA or the hilarious teenagers milling about the platform trying to be 'tough'. It might not look like it, but we're nearly at your oasis. Walk away from the shopping centre, in the opposite direction toward the gigantic glass pyramid. No, you're not hallucinating, there really is a giant pyramid hotel in Vienna. I've no idea why, but presumably the architect was recently returned from Vegas, high on inspiration to design a pyramid in Austria's answer to the Nevada desert - a dusty car park of the outer city suburbs.By now I can see that look in your eyes, you think I'm leading you into the middle of nowhere scrub land. I don't blame you. The first time Stefan brought me here I was overheated, hungry, my stomach growling and patience fading. I was convinced we were going to be murdered in this wasteland carpark desert. But I promise you, there is an ice-cream and happy ending to this adventure. See that rusted yellow sign up ahead? That's the entrance.Now take  a moment here, remember your scepticism and confusion because what you are about to see is Vienna's best hidden oasis.

100 Tage Summer

It's unbelievable right? The rolling green meadows of freshly cut, emerald green grass. The perfectly manicured walkways and polite sunbathing areas. That clear, fresh water! Follow me down this hill here, and pay no attention to the nearly-naked wrinkly old man there in the yellow speedos - the best part of 100 Tage summer is yet to come.

See there, through the crackly trees? The water is there yes, but more importantly there is an actual beach. With real, genuine small grains of sand that your toes can sink into and scrunchily walk across. None of the terrible rocks and dirt business you find at other lakes. And there, off to the right, see the white umbrellas peeking out? That's our home base. There's a bar, sun loungers, cushy sunbeds and sometimes even a live DJ. This is 100 Tage Summer.

A real beach bar 20 minutes outside of Vienna. We can chill here on one of the beach chairs if you like. Doesn't the view make the sticky trip worthwhile? We can look across the lake, and even though it's not the Mediterranean, it is one of the clearer, deeper lakes I've swum in, somehow it just feels fresher than the Alte Donau.

And there you have it - your personal guide to Vienna's best summer oasis. It can get crowded on busy days here, or so I'm told, but each time we've visited it's been pleasant and relaxed. You joining us for a swim then?

P.s Want more insider tips on where to go in Vienna? Get your hands on my Insider's Guide to Vienna for handpicked local recommendations on what to see, do and eat in the city.