Tallinn's Old Town is small enough to cross on foot in under two hours, yet most visitors only see one street of it. The trick is matching the walk to who you're with. Below are four routes — pick the one that fits your day, not a generic loop that suits nobody. Start at Viru Gate Photo by Vaido on Unsplash Every good Old Town walk begins at the same place: Viru Gate, the twin medieval towers with a flower market tucked just inside. From most of our apartments it's a five-minute stroll. Walk straight up Viru Street and you reach Town Hall Square in about seven minutes. Go early — the square fi…