Porter Airlines is a regional airline headquartered at Billy Bishop Toronto City Airport on the Toronto Islands in Toronto, Ontario, Canada. Owned by Porter Aviation Holdings, formerly known as REGCO Holdings Inc., Porter operates regularly scheduled flights between Toronto and locations in Canada and the United States using Canadian-built Bombardier Dash-8 Q 400 turboprop aircraft.\n\nAnswer this question: where does porter airlines fly from in toronto?
Please answer the following question by reasoning step-by-step.
Billy Bishop Toronto City Airport
This is the relevant information: Porter Airlines is a regional airline headquartered at Billy Bishop Toronto City Airport on the Toronto Islands in Toronto, Ontario, Canada.

.

The answer is Billy Bishop Toronto City Airport