Cannon Bar & Grill is one of two bars in the new Galle Dutch Hospital. It's run by the established Lucky Tuna (Unawatuna). It's a great location, but like most things in the GDH, it's bit average for the money you spend.
We tried a few things here, trying to get a sense of the place. A Long Island Iced Tea (Rs. 900), an Arrack Sour (Rs. 490), a Blue Lagoon (Rs. 550) and a Singapore Sling (Rs. 650). The cocktails were basically average. The prices overall weren't that bad here. A bottle of Lion here is Rs. 400, fyi. A glass of wine is Rs. 750.
We were on a bit of a bar crawl and we tried only one food item. When we do this we try to make it one of their main dishes, so we tried the Lucky Tuna Club Sandwich (Rs. 850). No joy here. Dry bread, meager toppings, no bacon or anything interesting really.
What Cannon does have going for it is a great location. If you get a table outside you have a lovely view over the ocean and down into the courtyard below.
There's more seating in the interior, plus a TV and the furnishings and generally ambience are nice. The Galle Dutch Hospital is a beautiful building and a nice place to hang out.
They were pretty busy when they visited and didn't pay super-much attention to us, but the service was generally OK.
Cannon is a cool place to hang out in the Galle Fort, but go for the location rather than anything special in terms of food or drink.
Through the main Galle Fort Gate: take the Church Street detour, turn down Queens Street, go through Court Square. From the Eastern Gate, turn onto Queens Street. It's on the second floor.