The outside patio could possibly be pet friendly I was on the outside patio yesterday and it wasn't too bad.
Every time I've been to the Metro Diner in Venice, it is far too busy for it to be a good environment for a pet, the staff is very attentive, and thus, they are moving quickly all around the restaurant constantly. Most tables are full on our visits. I don't think the inside of the restaurant would be safe for most pets.They do have some outdoor seating, which might be better for that purpose, but I would definitely call to find out for sure.
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