The hill-fort of Keava represents an example of the so-called promontory hill-forts; i.e. the fort is separated from the rest of the promontory with high walls and deep ditches, whereas the walls have been erected also on the longitudinal sides. The Keava promontory is situated in the direction of NE-SW, and the ancient fort was located on its higher portion. The height of the south-western wall of the fort is up to 2.5 m from the level of the inner plateau, and up to 6 m from the outer foot. The south-western ditch is 5-6 m wide and 1-1.5 m deep; it is located not directly on the foot of the wall but 6-7 m farther. The corresponding measures of the north-eastern wall are 2.5 and 6-7 m. Here, too, the ditch was dug 4-5 m farther of the wall, and it is now 3-4 m wide and 0.5-0.6 m deep. The height of the longitudinal slopes of the promontory is up to 20 m but the walls there do not exceed 1 m. In the north-western part of the hill-fort there is no longitudinal wall visible within 15 m. The plateau is oval, measured 55 m in the length and up to 20 in the width; the area of the plateau is around 900 sq. m. The surface of the south-western part of the plateau is gently sloping towards the end-wall, forming a natural depression on the inner foot of this wall.

In order to get some information about the cultural layer of the hill-fort a trial pit was dug into the north-eastern corner of the plateau in spring 2000. It came out that the cultural layer is 70 cm thick; the soil is black and contains both limestone slabs and small granite stones which bear traces of fire. Some fragments of animal bone and small pieces of pottery were also collected during this digging. In the depth of 70 cm there was yellow clayey sand unearthed.