My first trip to Orchard Park (grew up in Charlotte, NC) was for a preseason game in 1994, Bills vs. Redskins. I can't remember the final score but I know it came down to a field goal (seems like it was 14-13 or something like that). The Skins lined up for a game winner with a rookie kicker who was in camp, rather than the old vet Chip Lomiller. The kid missed the field goal and Buffalo won the game.
What made that game special was that I got to go with my dad who passed away about a year later with cancer. He's the reason I became a Bills' fan and I will always remember getting to go to a game in Buffalo with him before he died.
I didn't make another trip there until 2005, when my brother and I (who were both at that first game in 94) went up there together to see the Bills-Panthers 13-9 debacle. What a boring game to go see...but the entire experience was amazing.