Vostok 5 — piloted by Valery Bykovsky — and Vostok 6 — piloted by Valentina Tereshkova — were, like Vostok 3 and Vostok 4, a joint manned space flight.
Valentina Tereshkova was the first female cosmonaut.
Vostok 3 — piloted by Andrian Nikolayev — and Vostok 4 — piloted by Pavel Popovich — were the first manned space missions to orbit the Earth simultaneously and share communication by radio.