Sefer Ha’mitzvos Ha’Katzar (The concise book of mitzvos) By the Chofetz Chaim
This book lists the Torah mitzvos that can be observed today
Second Section – the Negative Commandments
7. It is a negative commandment not to go out of the techum (Sabbatical boundaries) on Shabbos
As it states in Shemos (Exodus) 16:29, “A person shall not leave his place on the seventh day.” This means a person should not walk out of the city more than 12 mil, even 1 amah more. This corresponds to the camp of Israel in the desert after they left Egypt. A person that transgresses this receives lashes according to the Torah. A person that walks more than 2000 amos, which corresponds to an open area of land from one city to another, receives Rabbinic lashes. This is according to the opinion of the Rif and the Rambam (but many early authorities of blessed memory rule that a person that walks many parsa’os does not transgress a Torah law, but a Rabbinic law). The 2000 amos is calculated as a square, which allows extra distance to be walked on the corners. Inside a city, it is allowable to walk throughout the whole city, even a long distance.
This applies in all places and at all times, for men and for women.