A valley where a runway used to be

Until a few years ago, the long strip of land in north-central Riyadh was an airfield, and its ground was flat for the sake of aircraft. Now the same site is being cut into valleys.

That is the surprise at the heart of King Salman Park. It stands on the former Riyadh Air Base, also known as King Salman Air Base, the city's old airport. Its facilities were demolished in 2021 and 2022. In their place the designers have been asking an unusual question: what did this land look like before anyone made it flat, and how can we bring a version of that back?

Borrowing from the wadi

The answer is the wadi, the seasonally dry riverbed that crosses the Arabian landscape and fills briefly when rain comes. Omrania's project page describes the landscape form as a series of branching valleys inspired by wadi beds, converging towards the centre. They make shaded, family-friendly places to gather, as RIBAJ also notes. In RIBAJ's description there are three zones: arid on the ridgelines, semi-arid below them and lush at the bottom.

Inside the circular Loop sits what Gerber Architekten, who led the landscape design, calls Central Park, with wooded areas, deep wadis and different garden and climate zones. The Loop itself winds between hilltops. According to RIBAJ, the widest wadi is crossed by skeletal bridges in weathering steel, and elsewhere the path runs over tunnels of reddish precast concrete.

Moving a mountain of sand

A valley is not free. To shape this one, contractors have moved a very large amount of earth. A Foundation executive reported that more than 13 million cubic metres had been excavated, and Illustrarch cites the same figure.

Holding the shapes in place needs engineering as much as landscape taste. On 14 May 2026, as reported by Al Madina from a Saudi Press Agency story, the Foundation announced that its retaining walls, known as MSE walls, were complete: 17 kilometres of them, built with 122,500 tonnes of local Riyadh stone. They hold the soil and shape the wadis, hills and plateaus, which are modelled on the Najd plateaus, and they create shade.

Water has a way of coming back

A park built in a wadi has to respect what wadis do. Gerber says the site was once a desert flood zone that has been transformed. A 2026 conference paper in the IOP series scored the park's flood susceptibility at 0.32, lower than the neighbouring Al-Uruba area at 0.38 and well below Wadi Hanifa. Overall the risk is low, but it concentrates in the low-lying drainage corridors, which is exactly where valleys sit.

The engineering reflects that. MEED reported in May 2024 that Haif's Phase 2 scope includes stormwater works and an emergency flood pond. Haif's contract, reported at about $480 million, began in November 2025, according to MEED. We have not seen drawings of the pond, so we cannot say where it sits or how much water it can hold.

A sponge underneath

The soil is part of the flood design, too. The park's team has described a regenerative soil layer about 2.5 metres deep, with biochar and pumice, in Arab News, and RIBAJ describes a matrix about two metres deep over bedrock. We give both, because the two sources do not agree to the centimetre. Its job is to act like a sponge, soaking up water and holding it for plants.

Valleys also make useful neighbours. One of the park's first private developments, Package 1, sits between two wadis, near the Royal Arts Complex and the Visitor Pavilion, per the Accor announcement. Gerber's list of park features also includes a Wadi Cascade.

What we are still checking

Several questions remain open. We do not have a published map of the individual wadis, and no official Arabic name for each one has turned up. Saudi Press Agency wording speaks of "wadis, hills and plateaus" in general terms. We also cannot say how the planned flood pond would work in a heavy storm, and the susceptibility figure is a single study, not a guarantee.

What we can say is that something unusual is happening. A flat, hard piece of land built for aircraft is being turned into a valley system that can shade people, hold water and, when it rains, behave like the wadis that were here before. If the design works, Riyadh will have a rare thing: a runway that became a river bed.