Consider carefully your route. View a map of the city and highlight all the most scenic and romantic places to walk in which is a pleasure. Pay attention to the ones that are near the girl's home. I don't think she will like the offer to go on other end of the city, even if it is something unusual. But if you've been Dating for a while, you can try to go somewhere further than usual.
Go for a walk with a girl in the city's largest Park. Even if this idea does not seem too interesting, your companion may love it. Nowadays, young people are busy at school or work, and rarely fails to walk in the fresh air, especially in the company of the opposite field. Well, if the Park has a pond, benches and lawns where you can sit together and chat in a cozy atmosphere.
Go to the embankment, if there is one in your city. This place is also quite romantic, and it is unlikely she will refuse to walk there. Especially beautiful to watch the water surface at sunset. Also, this may be your first kiss and even declarations of love.
Visit any event in the open air, such as a concert, theatrical performance, town festival, etc. Find out in advance which events will be held in the city on the day of your date and invite the girl to go together.
Organize a picnic, if the weather permits. Not necessary to go far beyond the city. You can sit at a comfortable clearing in the forest or Park, away from prying eyes. You will be able to spend more time alone and become closer to each other.
Invite the girl to stay active and go along for the ride on the bike or skis in the woods. So you'll be able to spend time with fun and health benefits.