The last time I saw Peter was when I ran into him at the station on my way to Glasgow.

I haven't seen Peter since a chance meeting with him at the station when I was setting off for Glasgow

The last time I went to Glasgow, I happened to meet Peter at the station.

When I last saw Peter at the station when I was on my way to Glasgow, I ran after him.

I finally saw Peter at the station when I was on my way to Glasgow.