Issued in 1973, this striking British commemorative set honors five legendary explorers who expanded the horizons of human knowledge. The stamps feature finely illustrated portraits of David Livingstone, Henry Morton Stanley, Sir Francis Drake, Sir Walter Raleigh, and Charles Sturt—each set against a map-grid background symbolizing discovery and navigation. Their lifespans are printed along the edges, with denominations from 3p to 9p. Designed with crisp historical detail, the set celebrates exploration, courage, and the enduring British spirit of adventure. A must-have for collectors of thematic “Exploration” or “Great Explorers” issues.