Translation:We went to the city after being at my house.
There's a lot going on in this sentence. First we have 'fuimos' so is that the past tense 'we were' or is it 'we went'. How do we know other than context? Because if it was 'were' we would have to use the past tense 'estar' not 'ser' because we are going to a location. So it's 'we went". We went is followed by the indirect object i.e.'ciudad' so we know it needs an article 'la' and the 'a' tells us its movement to the object.
Next part is a verb + de + estar. Here's a link that will help explain this concept. In essence we use this structure when completing an action or as a reflexive verb. http://spanish.about.com/od/infinitives/a/verb-de-infinitive.htm The infinitive is often changed to a gerund 'ing' as is estar to being. The rest I think we all know.
JenGresham - your welcome. Something I've learned along my spanish learning journey is that DL is very useful and at times it's worth it to change your 'method" . What I mean is that after so much DL it helps me to change to listening to audios, watching videos, and reading. It's more enjoyable this way and I feel I learn a lot better. I started off using DL for 100% of my learning experience and now I've changed that to 25% of my time and doing the other things to supplement my learning. I am not saying DL isn't great, I think it is. But listening is another form of input that starts to train your ear to listen to naturally spoken Spanish & rhythm of the language. Check online and you'll find lots of resources.
Very true. But in this case, "We went to the city after being at my house" doesn't sound weird at all to me. It's something we would say even in casual speech here (Canada).
Usually I know when some usage that is familiar to me is not completely standard for all native speakers, but this one surprises me.