Perfectly safe. We went in January and there was no sign of any trouble. Lots of great AirB&Bs, or I can recommend the aparthotel we stayed in, Hotel Arai, which was right in the middle of the gothic quarter with a lovely little pool on the roof.
It will be hot August - too hot for me personally, but depends on your tolerance of heat.
I don’t know about public transport because we walked everywhere or got taxis.
Thanks , we have to go in August as it’s school holidays and dh wants some sun . Kids are fine as long as we can pop in and out if shops/ museums which have air con . They have survived Orlando , Miami , New York and Washington over the past few years . Will look at that hotel thanks
We went to Barcelona and Stiges in July last year. It was hot and will be hotter in August. We all really enjoyed it. A good mixture of city things to do in Barcelona and then a friendly old fashioned seaside town with Stiges.
There is a good train service between the two places so can still day trip back to Barcelona. We liked the catalunya history museum. We also had a walking guide for a few hours which was very good and gave an insight to the city.
It's quite hot. The science museum is great. Have you thought about going and hiring a car? We've been to Palafrugell the last two summers which is lovely and then we've done day trips in Barcelona. Went to Port Aventura, the adventure park, last year as well which was incredible once we brought the fast pass thingys.
We only went to the main park, we only had one day and were staying 2 hours drive away. If I went back I'd probably spend a night there, there is one rollercoaster at Ferrari world that looked amazing.
FYI, if the kids are too small to do the main roller coasters the fast pass is even better ;) we managed to get two turns each on the two biggest rollercoasters whilst the other fed the kids candyfloss.
We went to cambrills in august last year and did a day trip to barcelona, it was hot. The train was easy although long, two hours I think, it stopped off at stiges.
Re safety, this isn't quite the same as you were referring to safety in barcelona rather than stiges but we were staying within a 5 minute walk of the confrontation in cambrills and even walking around the next day felt safe. They had an increased police presence in cambrills immediately after the barcelona attack and I imagine the same in stiges, salou and the other coastal touristy area's so I'd say catalonian police are responsive.