Asking an old friend to date from a long distance

I have know her for 6.5 years. I have had a crush on her for the majority of the time we’ve known each other, and I have gotten the same vibes from her in the past. I’m cautious, and don’t want to ruin a good friendship. We met in college and have been best friends ever since. We saw each other on a daily basis. She graduated about 3 years after we met and moved to another state. After she moved, we talked infrequently. I graduated and got a job about 6 hours from her. My group of friends from college try to get together annually and catch up. We recently got together for one of our meetings, and I realized how much I like her. Shortly after, I was told by a friend (who is also a friend of my crush) that she was waiting for me to make a move.

So I’ve resolved to ask her out, and have already planned on visiting her in about a month. The complexity of my situation is that we haven’t been communicating on a regular basis for a long time and we can’t easily get together. It doesn’t help that I found out that she’s waiting for me from someone else; it could be rumor! I have considered just calling her up and telling her how I feel before I go visit her, but have reservations about that because of the lack of recent communication. I also think this option is shallow, I’d rather ask in person rather than over the phone. I have also considered sharing how I feel while I’m visiting her, but I don’t want to catch her off guard. Since we are both introverted, she’d appreciated a heads up before I bring this up. I’m just not quite sure how to go about asking her out now.