Island access times are not universal.

It depends entirely on which islands you mean. There is no standard opening and closing for “the islands” — that’s like asking what time all parks close.

If you’re asking about a specific place like the Toronto Islands, those are accessible by ferry with set schedules (usually first ferry around 6am, last ferry around midnight), and the park itself is open dawn to dusk with gates locked at night. For national park islands, they are typically day-use only and close at sunset. For private island resorts, they may be accessible 24/7 to guests.

Your best bet is to search the exact name of the islands plus “hours” or “access.” Anything else is guessing.

Always check the official site before you pack for a night there.