US Night and Relay Championships Map Notes
1:10,000, 5m contour interval; ISOM2000 symbol set
This area is well known to long-time orienteers, but hasn't been used for national competition in quite
some time. It is quintessential Midwestern terrain: small to medium sized ridges carved with complex
reentrant systems. Woods are predominantly open with some thick spots. White woods range from
fast to very fast. Light green is slower with less visibility, but generally not worth going around. The
boundaries from white to light green are typically vague. Medium green is much better defined and
the boundary is usually visible from a ways off. Dark green is also easy to spot and you don't want to
go there. In many cases, there is a thin layer of light green between white and med/dark green. This is
not mapped unless it makes the more significant boundary difficult to see. Vertical slash indicates the
presence of thorns or significant deadfall. Neither is much fun, especially at night.
Rough open is fairly fast unless accompanied by vertical slash. There are a few old fields where young
forest is forming creating a "mottled green" of rough open and very dense woods. Where the
passageways are clear enough that accurately following them is a reasonable strategy, they are
mapped as rough open through the green. In the more typical case where the breaks are very narrow
and twisty, the whole area is simply mapped as medium green. Get through it best you can or go
Big Sugar Creek runs along the western edge of the competition area. Some courses may cross it. The
stream bed is wide and very distinct. It is mapped as sandy ground though it's primarily small stones. If
you're really good at uneven surfaces, it's reasonably fast running. If you're prone to twisted ankles,
you probably want to stay in the woods. The actual path the water takes changes dramatically with
stream level. It is mapped reflecting normal fall levels, but it could be anything from completely dry to
having the entire streambed underwater. Crossing is easy except in areas where there is a bank line.
Rootstocks are only mapped if they are really big (>2m). Fallen trees are not mapped.
All roads in the competition area are 20mph park roads. Still, look both ways before crossing.
There are several sets of wooden steps heading east from the lake up to the campground on top of
the ridge. These are mapped as large trails, and give comparable speed benefit going up (not so much
going down). As they have railings on both sides, they are not particularly easy to cross.
Creve Coeur Lake
1:10,000; 5m contour interval; ISOM2000 symbol set
This area is predominantly open forest on flood plain. White woods are very fast. There is a fair bit of
deadfall. Most of it is easy to get over or around. In cases where macro route choice could be affected
by deadfall, it is mapped with vertical slash. Light green is significantly slower than white. Dark green is
essentially impassible. Rough open is slower than white.
This time of year, water features are very dependent on recent rainfall, of which we've had almost none.
As of October 14 nearly all water features without bank lines are dry and this is not likely to change until winter.
The mapping reflects the depth of the feature, that is, how distinct the drop is from the surrounding
Note that mapped water features are still recognizable as water features even when dry in that the ground vegetation
indicates at least a history of annual standing water. There are areas that are "lumpy" from very old erosion
but there is no confirming watercourse. Such undulations are mapped with form lines if they are in excess
of 1.5m, otherwise not mapped at all.
- Intermittent and linear marshes: 0-20cm with no distinct edge
- Intermittent stream: 10-30cm with a more defined edge
- Stream: 20-100cm with clearly defined edge
- Large stream: 50-200cm and at least 3m wide
All of the above-mentioned features are crossable, even when it is wet. Regular marshes and ponds without bank lines
are also crossable, though you'll probably carry a fair bit of mud on your shoes for a while. Streams,
lakes, and marshes with bank lines are difficult to cross and should not be crossed due to
environmental reasons. Courses will be set so that there is no advantage in taking a route that crosses
a bank line.
The main power line running through the park is strung along typical high-voltage towers. However,
these are offset in such a way that using the large power line symbol would prevent showing accurate
placement of the towers. Thus the regular power line symbol is used. Small power lines are not
A sufficiently agile orienteer could cross fences mapped as uncrossable. Courses will be set so there is
no advantage in doing this, but it's legal unless the area on one side of the fence is mapped as
permanently out of bounds (vertical black lines).
The Page Avenue Extension is a 10-lane highway that bisects the map. The highway itself is strictly out
of bounds. Where the highway is elevated, the road is not shown, just the concrete supports (mapped
as rock pillars). You are free to run under the overpass (on most courses you will have to). Where the
highway is on the ground, it is mapped as permanently out of bounds; you MUST go around.
Rootstocks are either very large (>2m high) or sufficiently isolated that they shouldn't be confused
with other unmapped deadfall. If the tree has decomposed to the point where the only thing
remaining is the root bump, it is mapped as a dot knoll.
The one tree stand (Black "T") on the map is actually a fairly large bird house on top of a pole. It looks
like a tree stand from a distance. Other miscellaneous man-made objects are mapped with the
ubiquitous Black X. The mapping standard for such an item is that it is visible from a distance (25m or
so), is the largest man-made object in the immediate vicinity, can't be easily moved by two people,
and is clearly man-made. Failing this last criterion is a shelter made from a fallen tree and driftwood. It
is mapped with a black "O".