The minelayer Olev is a vessel of the Estonian Navy Mineships Division and also the third modernized Frauenlob class minelayer. In 2003 a cooperation contract was signed between the Paldiski city council and the minelayer Olev which gave the vessel a right to wear the Paldiski town coat of arms and to introduce the city in all foreign harbors across the world.
The Olev (M415) was built in West-Germany, in a Krogerwerftshipyard in Rendsburg. The vessel was launched on the 13 December 1966]] and she entered service a year later on the 21 September 1967. The German Navy decommissioned Diana and two of her twin sisters Minerva and Undine in late 1990s and gave the vessels to the Estonian Navy to operate. On the ceremony the vessel received an Estonian name Olev.
<gallery><!-- Deleted image removed: Image:ENS-Olev-02.jpg|Olev´s crew training --><!-- Deleted image removed: Image:ENS-Olev-03.jpg|Olev on a patrol --></gallery>