This is what I wrote into my decline log - sorry that the e-mail didn't reach you:
===
Sorry, this is not a geodetic point - this sign means that a water or
gas pipeline is buried there, and how deep, I don't know the exact
meaning of the numbers. The geodetic point would usually have a
red&white pole and a granite block - see the other waymarks in this
category.
===
The second picture is a temporary mark used by surveyors, you can find them nailed in the pavement. They are not in the CUZK (Land Survey Office) database and they don't qualify for a WM.
You can prepare your hunt with the map at
cuzk.cz - the waymarkable points are
,
and
.
A typical geodetic point in the woods looks like this (
WM75D6):
Some of the points are church or castle spires, eg.
WM750P:
The yellow squares on the map are the gravimetric points - usually a concrete square like this one(
WM4PVE):
