OnlyBLR #1

 Below is a wikipedia description about famous Bangalore monument X.

"Kempe Gowda II (who came to power in 1585), the feudal ruler of Bangalore, is credited with building four watchtowers setting limits for Bangalore's expansion, which included a tower on the X (on the southern boundary) as it commands a panoramic view of Bangalore city. It is said that at sunset a sentry would blow the X and hold a torch which was visible from the other three watch towers (one on the southern bank of the Kempambudi tank on the west, the second near Ulsoor Lake in the east and the third tower adjoining Ramana Maharishi Ashram on Bellary Road, namely Mekhri Circle in the north). This was done to inform people that everything was safe at that location and to give a warning X call to alert the citizens of any intruders into the city. Most of the rocks on the X, next to the Bull Temple, have hollows, which were once used to light lamps. This landmark spreads over an area of 16 acres (6.5 ha). This X is contiguous and similar to the rock at Lalbagh tower."

X is either the compound word meaning, together, "Trumpet, (the solid mineral material forming part of the surface of the earth and other similar planets, exposed on the surface or underlying the soil)"

ID X?

(the picture is the watch tower built by Kempe Gowda)