Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_18118221_1 (rank INTEGER, railway_station VARCHAR)
### Question:
What is the lowest rank of Gatwick Airport? 
### Answer:
SELECT MIN(rank) FROM table_18118221_1 WHERE railway_station = "Gatwick Airport"