<a href="https://en.wikipedia.org/wiki/Space_Race" id="mwAQw" rel="mw:WikiLink" title="Space Race">Space Race</a>: Soviet spacecraft <i id="mwAQ0"><a href="https://en.wikipedia.org/wiki/Soyuz_4" id="mwAQ4" rel="mw:WikiLink" title="Soyuz 4">Soyuz 4</a></i> and <i id="mwAQ8"><a href="https://en.wikipedia.org/wiki/Soyuz_5" id="mwARA" rel="mw:WikiLink" title="Soyuz 5">Soyuz 5</a></i> perform the first-ever docking of crewed spacecraft in <a href="https://en.wikipedia.org/wiki/Low_Earth_orbit" id="mwARE" rel="mw:WikiLink" title="Low Earth orbit">orbit</a>, the first-ever transfer of crew from one space vehicle to another, and the only time such a transfer was accomplished with a <a href="https://en.wikipedia.org/wiki/Extravehicular_activity" id="mwARI" rel="mw:WikiLink" title="Extravehicular activity">space walk</a>.