This first day cover commemorates the opening of the Post Office Tower in 1965 during the reign of Queen Elizabeth II. It features a stamp depicting the iconic tower, which was the tallest building in London at the time. The cover is cancelled with a special first day of issue cancellation, making it a unique addition to any stamp collection. The cover is in used condition and was issued during the pre-decimal era. The cancellation type is first day of issue, indicating its significance as a collectible item. Its topic is communication, reflecting the important role of the Post Office Tower in facilitating communication and broadcasting. Overall, this first day cover is a must-have for any stamp collector or history enthusiast.