I booked the "Hidden Athens" tour through Viator who subcontract to this company. It was our first day in Athens and unfortunately it was National Day. The entire centre of the city was closed down by armed police at every corner and it took us half an hour to work our way around the cordon to the rendezvous where Kostas was waiting for us. Fortunately for us, the other party did not make it so we had Kostas to ourselves. With the military parade on, he was more than happy to take time out from the tour and, as an ex Presidential guard, he was a terrific commentator for the watching of the parade. When we had seen enough we resumed the tour itself which takes in some hidden parts of the Plaka that we, as ordinary tourists, would not have found. We thoroughly enjoyed our time with him and felt like we were parting from a friend at the end of our time. He has a number of different guides on his books and we had no recommendation in recommending his company to fellow travellers along the way, who reported back favourably.