Kiwi can easily walk up to 2-3 miles when the weather is good.  I have never had to pick her up, she always keeps up with me and my hubby even when we walk briskly.  Barring health problems, yorkies have so much energy and just love to go!  She has no problem when we go on longer hikes in the state parks around here, even up to 4-5 miles!  If she did, we would just carry her.
