When treading the path of the western world’s greatest pilgrimage, the typical walker cannot help but peek — OK, stare — at the sandy-gray “mileage” markers that helpfully guide everyone along.

They serve three functions for those headed to Santiago de Compestela, and the cathedral there.

–They “brand” the route. The yellow scallop shell is the symbol of the Camino, and its placement inside the blue background, on the upright pillar, tells the passerby “you are walking the Route of Saint James”.

–They point the way. The yellow arrows indicate the correct choice of direction. To that end, the hundreds (thousands?) of pillars get pilgrims to Santiago. They appear at every “either/or” moment of the walk. The arrow means “this way, not that”. This is a vital function because the pilgrims often march through rural areas or empty territory without street signs — or even streets — and sometimes with few, if any, people around.

–The pillars count down the distance to Santiago, from the number plate fitted into it. In the photo (above) you can see the numbers below the yellow arrow. In this case, we were 24.429 kilometers (15.179 miles) from Santiago. (A few strides later, we were 24.428km from Santiago. Etc.)

We Americans tend to call them “mileage markers” … but the Camino is on the metric system, and the distance remaining always is taken out to the third decimal.

For those of us on the Camino, we know the walk’s “brand” and we follow the yellow arrow without hesitation.

What changes is the distance marker, and it is our friend and enemy.

Some of us have the ability to just cruise along the walk, admiring the scenery, chatting with friends (or momentary friends) on the trail.

Many others of us, however, are constantly updating ourselves on how many kilometers we have gone so far that day, then doing the arithmetic to inform everyone how far we have to go till the next resting or snacking or sleeping point.

Any progress should be hailed, but sometimes announcing the distance can have a dampening effect, when it seems as if we are getting nowhere fast. On the whole, to be able to say, “ah, but we have gone 3.4km already today” can buck up the peregrino whose dogs are barking and it ain’t even noon.

(Oh, and fyi: The rocks atop many of the pillars, in the photo above, are meant as tributes to people no longer living, left by relatives or friends.)

As we checked in at our pension in O Pedrouzo, the last stop before Santiago, I noted, reflexively, that the previous pillar we saw indicated we are 19.7km short of the cathedral.

Thus, we can calculate how fast we need to walk, when we start on the trail today, if we want to attend the special pilgrim’s mass at noon. Earlier start, slower walk. Later start, power walk.

The numbers in the pillar tell us all we need to know.

They are so very handy for the pilgrim on a schedule, including this one, who hopes to complete a second Camino in time to see the botafumeiro swinging in the great cathedral.