Do something fun. What do you both consider fun?
Sitting and talking puts a lot of pressure on you both. Keep things light and fun on the first few dates. If you hit it off really well, then you can talk more and get to know each other better...gradually, over time. For now, avoid too much pressure.
If you both like to talk, then go to a coffeehouse or diner or someplace you can lounge a while and just eat, drink and talk. But ideally I'd say do the fun, active thing first, and then go someplace to eat if it went very well. Because the ice will be broken (tension gone). If you both feel awkward and have no activity planned (even a movie would be OK), then you might end up just sitting and staring at each other uncomfortably.
Don't plan an athletic date though, unless she has said she loves that type of thing. Most girls do not want to get sweaty and stinky on a date, especially a first date. If she loves to hike though and so do you, that's different.
More clues as to what your personalities and likes are, would help. 