Past simple or past perfect

Last year we 1. went on holiday to Buenos Aires. We 2. were very tired and quite dirty when we 3. arrived because the plane 4. left six hours late. When we 5. got to the city cente we 6. looked at the map which travel agent 7. gave us in London. We 8. walked along the street and 9. found our four-star hotel. When she realised she 10. made a mistake, she 11. was very embarrassed!