2.
First, when I was 11 and had missed the bus to school. I was terrified (first time I'd got the bus alone and I had no idea where to go if I missed it) and sat at the stop crying for about a hour. A lovely old lady stopped to help me, made sure I got the next bus, told me which stop I needed to get off at and gave me directions so I could get to school. Turns out my mum had panicked when I didn't show for school (as mums do) and the head of year was out looking for me!
Second was when I went to buy a new car in Manchester last year. I don't know the city and I thought my new car had broken down on the way back (turns out it was fine in the end). My phone was dead and I was lost in the city centre at about 10pm in November. A man and his wife/girlfriend stopped to help me, calmed me down, let me borrow his phone to call the AA and even gave me £3 so I could use the nearby phonebox if I needed to. He offered to wait with me 'til they came, but I couldn't ask him to do that when he'd done so much already! I can't thank them enough - I wish I'd taken his name and address so I could have repaid him.