My mother died when I was 23. Many of my childhood friends knew her because of her involvement in youth choirs & church. Only a few actually came to the visitation/funeral...pretty much the ones who still lived in the town where we went to high school. Most of the people there were family and friends of hers & my father's in their own age range.
What I really appreciated was the out of town friends who took the time to send me a card, and took the time to write in it (not just a schmaltzy prefab sentiment). May I suggest you do the same? Travel like you mention is generally reserved for someone who was a "second parent", or a family member.