Point culminant de la Haute-Marne

The highest point in the Haute-Marne is exactly 523 m, at the place known as "Haut de Baissey", in the wood of the same name. Approximately one kilometre to the north is Haut du Sec, which rises to 516 metres and, free of tall vegetation as you approach the small road, provides a view of the Langres plateau and the city of Lingonne. The microwave relay located there can link over 36,000 telephone lines between Paris and Lyon.

For nature lovers :
Vegetation:
The Haut du Sec grassland at Perrogney-les-Fontaines occupies one of the summits of the Langres plateau and was declared a partial Voluntary Nature Reserve in 1987 (covering around 17 hectares). A number of rare plant species of southern or central European origin can be found here, four of which are protected at regional level (whitish helleborine, close to the limit of its range, bird's-foot sedge, germander broomrape and rock violet), nine are on the Champagne-Ardenne red list of threatened plants (including Apennine helianthemum, humble sedge, common fumana, Salzburg euphrasia, thyme broomrape, etc.One species is close to the northern limit of its distribution (Ptychotis saxifraga). The mountain inula, once reported on the site, has now disappeared (and has certainly disappeared from the whole of Haute-Marne).

Fauna:
The entomofauna presents the same biogeographical tonality as the flora, with various butterflies characteristic of this type of environment, three of which are on the red list of Lepidoptera in Champagne-Ardenne, the sanguisorbe peacock, the mead fadet and the blackthorn thecla. Uncommon orthopterans on the regional red list also frequent the site: crickets (including the Italian locust, the blue oedipod, which is very rare in Haute-Marne, the wandering locust and the small-winged locust) and grasshoppers (white-spotted platyceis, small-winged decticelle and vine ephippiger), with a total of 11 red-listed species. The praying mantis and the small mountain cicada are also found here. The pigeon, a rare and declining breeder that is on the regional red list, is present on the site. The area, most of which has been replanted with pine trees, is very overgrown, and has been renovated by a youth work camp run by the Nature Haute-Marne association.