How 27 Crags grew into the Topo: a sustainable social platform for the climbing community
It feels apt that rock climbing is what saved, what was then 27 Crags, a climbing guidebook app. Ville Muittari, the current CEO, met the original founder on a climbing trip. There, he learnt that the platform, which then existed just as a website, was on the verge of shutdown. His reaction was: "Hell no! All my ascents* are logged there. Don't close it, I'm going to figure something out!"
His reaction was: “Hell no!” Terrified he’d lose his entire history of climbs and plotted routes, which were stored on the platform, he said: “Don’t close it, I’m going to figure something out!”
Back then, the site had no real business model. Its only revenue stream was a few ads, which brought in a few hundred euros a month, if that. For the previous owner, it was just a hobby project that had become unsustainable when server costs went up. "There was just too much to handle for one person," says Muittari.
He didn't know how he was going to save it until, on another climbing trip in 2014, he met a local climbing guidebook author from Athens, who was having problems with the distribution of his guidebook. Now, as Muittari puts it, there were “enough issues”; he could use one to solve the other.
Muittari, who’s now been at the platform for 13 years, replaced the wavering advertising revenue with a subscription model ("of course, there was resistance") and used half of the subscription fees to pay authors – like the Greek writer he'd met up a mountain – to update and add new routes. Building safe climbing guides isn't your standard community-driven content, it means taking photos of the topography and drawing out every route up it, from easy to hard.
"People want to share their knowledge, as long as it's fun," says Muittari. But although the app is fast to use, mapping out all of the 500 routes in one bouldering area can take days. "And that's not fun anymore."
“Our core is that we want to make it easy to go climbing.”
Ville Muittari, The Topo
So, to ensure that climbers get all the routes they want, the platform offers compensation to those who put in the effort. In 2025, the 500-odd route authors were paid roughly €300,000 between them. For most of them, that's enough to fund their work on new routes, but a few superusers are actually making a living from the money they earn from the platform. And they're worth the investment.
“Prioritise your core.”
Ville Muittari, The Topo
As another founder and investor Florian Meissner explained on stage at Rebuild 1: "If you understand what transactional value your community offers, and you double down on it, you succeed and you make money eventually."
For the platform, the advantage is a huge set of proprietary data, annotated images of rock climbing paths, which is hugely valuable because it's so hard to replicate. But that's not Muittari's motivation: "Our core is that we want to make it easy to go climbing," he says. "So everything, every feature, what we do, should serve that one purpose." Having this central principle to focus on and build from, helps keep them focused. Seven people keep the platform running, but the users still expect the same bug-free experience they get on the huge apps made by Big Tech. "So we have to reduce the number of features," he says, "prioritise your core."
The next phase of development is adding a social element. Muittari isn't exactly sure what it will look like yet, but suggests a sort of matchmaking service for belaying buddies. He's not expecting it to happen overnight, pointing to Strava, which has a social element now "but it wasn't always like that".
That echoes his advice to builders starting out now: "Don't give up! If you believe in what you are doing, if you love what you are doing, don't give up, just keep on pushing." "Building that critical mass might take time," Muittari says, "and you might fail, but you just need to keep going." Now, the startup's estimated revenue for 2027 is €1.4m and in April 2026 it changed its name to "The Topo". The platform got its original name from hosting topos from 27 crags back in 2008. Today, the platform has 5,000+ topos from local authors worldwide and 50% of subscription profit goes back to the people who create them. A name change to reflect that seemed in order.