More than 80,000 workers were engaged on the construction of the park. CLM Delivery Partner - a joint venture of CH2M Hill, Laing O'Rourke, and Mace - managed the white space between the venue zones and the internal road network. The EDAW Consortium designed the park itself, with EDAW, Allies and Morrison, and Buro Happold leading the team, supported by Arup and WS Atkins on engineering, LDA Design with Hargreaves Associates on landscape, and Speirs and Major on the lighting. The planting design came from Professors Nigel Dunnett and James Hitchmough of the University of Sheffield together with garden designer Sarah Price, who created the now-famous large-scale naturalistic perennial meadow schemes that turned the park into a wildflower spectacle during the 2012 Games. The aim was a park that would outlast the Olympics and become a permanent neighbourhood resource.

While the soil was being cleaned and the pylons taken down, archaeologists found a Roman village beneath the future park. The Lower Lea Valley has always been edge-land - too marshy for stable settlement, useful for the things cities prefer to keep at the edges, but humanly important all the same. The park straddles four east London boroughs: Newham, Tower Hamlets, Hackney, and Waltham Forest. The postcode is E20, a designation that had previously existed only in the fictional Walford of the BBC soap opera EastEnders. Royal Mail simply made it real. Five neighbourhoods of housing and amenities sit within the park: Chobham Manor in Newham, East Wick in Hackney by Hackney Wick, Sweetwater in Tower Hamlets, and Pudding Mill and Marshgate Wharf in Newham. The names come from the area's history rather than its developers' imaginations.

Anish Kapoor and Cecil Balmond's ArcelorMittal Orbit - a twisting red steel observation tower that has become Britain's largest piece of public art - watches over the park from its centre. The London Stadium, now home to West Ham United Football Club after a long legal dispute involving Tottenham Hotspur and Leyton Orient, hosted the 2017 World Athletics Championships, Rugby World Cup matches in 2015, and the first Invictus Games in September 2014. The London Aquatics Centre, designed by Zaha Hadid, hosted the 2016 European Aquatics Championships. The Lee Valley VeloPark hosted the 2016 UCI Track Cycling World Championships and later cycling events at the 2022 Birmingham Commonwealth Games. The Copper Box Arena, the only permanent indoor arena to survive 2012, became home to the London Lions basketball club from the 2013-14 season.

In 2021, ABBA began construction of a purpose-built venue in the Olympic Park. Called the ABBA Arena, it opened in May 2022 to host ABBA Voyage - a motion-capture hologram concert residency in which digital avatars of the four members perform a setlist as their younger selves. The announcement came during the YouTube livestream of the band's album Voyage. The Olympic Park has gradually become a creative district as much as a sporting one. The Stadium has hosted concerts by Guns N' Roses, AC/DC, and Robbie Williams. The former site of the Riverbank Arena hosts the Hard Rock Calling, Wireless, and Electric Daisy Carnival festivals each summer.

The most ambitious legacy of the 2012 Games may be East Bank, a GBP 1.1 billion cultural district under construction at the park. The Victoria and Albert Museum is opening V and A East in April 2026, under director Gus Casely-Hayford, with a programme aimed at younger and more diverse audiences than the museum's South Kensington home. University College London opened its new UCL East campus within the park in 2023. The BBC has relocated its famous Maida Vale Studios to the park, where they will continue recording music for new generations of broadcasts. Sadler's Wells will open a dance venue here too. What was the Lower Lea Valley - a marshy edge-land with pylons and Roman foundations - has become a place where Olympic history, world-class housing, holographic ABBA concerts, and one of the great museums of the world all share a postcode. The park reopened in stages from July 2013, with the Aquatics Centre, VeloPark, and Orbit returning to public use in April 2014. The wildflower meadows still come back every summer.