I am looking for ideas of where to go from Barcelona with Public Transportation only.
I will be in Barcelona from 6/28-7/1. What is within travel to and from in a day while I stay in Barcelona? Or should my base be out of town? I will be arriving in Barcelona by bus from France and flying out of Barcelona.

a day trip by train to Montserrat is worthwhile.

Second the rec for the trip to Montserrat

Another suggestion is Sitges, a chic seaside resort only 35 min away by commuter train and costs only 2.80 euro one-way (zone 4). Avoid sunny weekends as it will be mobbed!
Girona, about an hour by train, is a Roman city with a compact historical centre. From there, you can get to Figueres (on the same rail line) where there is famous Dali Theatre Museum. From Barcelona, take Catalunya Express from Sants station, which costs 7.05 euro to Girona, 10.30 euro to Figueres one-way and takes about 90 min and 2 hours respectively.
Costa Brava is also a possibility, but it's at least 2 hours away by bus (no train) and without own transport you may not have enough time to explore many fascinating villages and coastal roads.

Thanks for the Replies, especially with the details of what bus/train to take and how much it cost.
Please keep them coming.

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