Similar to tours there are other activities you can participate in to meet people. Cooking classes or yoga lessons come to mind. They have the added benefit of teaching you about local culture and customs while being social and meeting people from all over the world while sharing experiences.
This might be pubs, bars, restaurants, community centers. Of course to connect with locals in places like that you will have to be an extrovert, able to go up to people and start a conversation.
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