This pin commemorates city of Leningrad (St Petersburg) as a "cradle of revolution".

1967 was 50^th anniversary of Great October revolution (official name for coup d'etat of 7^th November, 1917 - 25^th October by Old Russian calendar style).

In the background you see a map of streets around Winter palace, which was stormed by revolutionary troops on that day. Remarkably, there were only 6 dead - as most of Winter palace defenders fled away. And the only unit, holding up was "women battalion of death volunteers" - composed mostly from widows of St George cavaliers, KIA during WWI.

A. F. Kerensky - a head of Provisional Govt, has fled the city in woman dress. The irony...

By 1967 official party line was that it was Lenin who (sort of single-handedly) has led Great October revolution. In 60s there was resurgence of "leninism" - when Lenin role was idolized (as opposed to quite recent personality cult of Stalin).

Hello! I'm not a historian, but since I was born in USSR, there some things on this pin that are quite noticeable.

1. On the very bottom it's written ЛЕНИНГРАД|LENINGRAD, so apparently it was made in Leningrad (now St. Petersburg)

2. On the very top there are 5 medals. They represent 5 awards that were given to Leningrad. For example, on the very left there is "Gold Star" - award, usually given to the Heroes of the Soviet Union. Leningrad was declared Hero City in 1965 and given that medal.

I've checked at the wikipedia, it seems that Leningrad had 5 medals, latest of them was given in 1967, so this pin was made after 1967.

3. In the middle you have a statue of Lenin. On the background you can see the plan of central part of Leningrad, the heart of two Russian revolutions of 1917.

So that's all I can say.

It's a pin commemorating the siege of Leningrad 1941-44.
EDIT: I stand corrected, then. See above.

These types of pins were readily available to the average Soviet citizen and could be purchased for a nominal sum at newspaper kiosks. Throughout the entire Eastern Bloc, these types of "civic pride" pins were very commonplace, even smaller towns of 20,000 often had their own. Many of these combined civic identity with some important event, such as an anniversary of a military feat, life of a notable person, a party rally/congress or a sporting event. Since their production was entirely in the hands of the state, they were an excellent publicity/propaganda tool. For example, at the time of the 1980 Moscow Olympiad, the "Mishka" mascot pins were readily available well in advance of the actual games, not only in the USSR, but across the Eastern Bloc. They were very collectable - while growing up behind the iron curtain, many of my childhood friends boasted of not only Soviet but also Czechoslovak, Polish, East German and Hungarian pins in their respective collections.