June flips the map north. Northern Europe wakes up with 14-20°C days and white nights, while the Mediterranean turns hot and closes its beaches to dogs from May through September. Stockholm, Copenhagen, Helsinki, Tallinn, Bergen and Edinburgh hit their stride now, with long light and an outdoor culture built for dogs on leash.
Stockholm and Helsinki open their archipelagos by ferry, dog aboard. Sweden also carries some of the EU's lowest pet-travel supplements, a nice bonus for longer stays. Edinburgh stays cool and green without the UK's summer heatwaves, and the Baltic capitals add cobblestone charm with mild, dry days.