Estonian here. Our nature is kinda similar, but a bit different and we have great hiking routes you can view here. So any EUians here who don’t go through the hassle of getting a UK tourist visa or whatever is required (because, y’know, brexit; I’m not too familiar with the actual requirements tho), you can come here instead. I’ll tell ya, OP’s photo looks like it could’ve easily been from the south-eastern section of the Peraküla-Aegviidu-Ähijärve route. I’ve only done about 400 km of that route because I joined the group after they’d done the initial part, but I can tell you, it’s great.
Bonus points: Around late june, early july, it barely gets dark and only for 2-3 hours a night (time between sunset and sunrise is 6 hours, but it doesn’t go dark immediately, and it starts to brighten up way before sunrise too). You could pretty much hike all night if you want, or do what we do, and have massive summer solstice celebrations all night on the night between the 23rd (our Victory day) and 24th (St. John’s day). Get drunk, make shashlik, jump over a bonfire, etc.