Great Atmosphere and good beer. Lost Rhino is among many small breweries that are slowly taking over Ashburn as what makes the area popular. When you first come in the serving bar is inviting to grab your beer and then move on to find a comfortable spot to site. In addition you should check out the back room where you can find more space and where local musicians will come in to periodically play.
As far as the beer goes Lost Rhino is Pale Ale central and tends to be not very good at making Hefes' or Wheat beers as competing breweries in the areas. However if you are a IPA fan then Lost Rhino is probably the place for you.
The craft brew scene is great up here in Virginia. I've come across this brewery just by chance with some friends & I have to say it was amazing. If you're into IPA's, you should definitely give this place a try.
PS - Can we leave the kids at home please? A brewery is not a playground and no one wants to listen to crying kids or try to avoid their aimlessness while navigating through a crowd with hands full of beers. Also, good job drinking and then driving around with kids in your vehicle.