MB4 262a: Your Property and Hilchos Techumim (397:1-5)

In addition to a person's four amot in each direction, one has 2000 amot in every direction on Shabbos (techum). The four amot include the city where you are at the beginning of Shabbos.

Measuring the 2000 amot on Shabbos.

Techumim applies to one's property as well, even if another person can go beyond your techum he can't take your items beyond your techum. If you give over an animal to your son who's techum does the animal follow? What if you give sheep over to a shepherd (Jewish or non-Jewish)?

Is techumim d'oraita? Does it apply on on Yom Tov?