My wife and three sons (6, 8 & 13) had a fantastic and entertaining tour with Dr. Yohannes Zeleke for four hours. We wish we could have spent four days with him. We arranged the tour through Groupon and had no problem coordinating with him to get started. The depth and breadth of his knowledge, coupled with his humor and warmth, made the tour unique and remarkable compared to the other tours we took in DC during this trip. I wish that more tour guides had the education and passion of Dr. Zeleke. If you only can take one tour of DC, this should be the one.