A soldier in the United States Army, when marching, uses a 30-inch step. That is roughly equivalent to three quarters of a meter.

I have seen many captains, majors, first sergeants, and sergeants major pace off the dimensions of a field when allocating space for a company or battalion to camp.

A viking may use a similar strategy. I have laid two two-meter horizontal beams on the ground end to end and then counted the number of seconds it takes me to traverse that four meters at a walk (toggled with the C key). For a square or rectangular area, it is then easy to place a corner post and then pace off the desired length and width.

The margin of error seems to be two or three meters but once one knows the number of seconds walking four meters takes, one cam dispense with laying out beams. One needs only corner posts.