Nairobi Southern Bypass Closure Set for May 10 Marathon

Key facts

• Nairobi Southern Bypass to be closed on Sunday, May 10, 2026.
• Closure affects the stretch between Ole Sereni Interchange and Lang’ata Road Interchange.
• The road will be shut from 6:00 am to 1:00 pm.
• The closure is to facilitate the 2026 Nairobi Marathon.
• Alternative route: Mombasa Road (A8) to Nyayo National Stadium Roundabout for Lang’ata Road access.
• Kenya National Highways Authority (KeNHA) issued the public notice.
• Motorists are advised to cooperate with traffic police and marshals.

Traffic Disruption for Annual Marathon

Nairobi motorists face significant traffic interruptions on Sunday, May 10, as a key section of the Nairobi Southern Bypass will be temporarily closed. The Kenya National Highways Authority (KeNHA) has announced the closure to accommodate the annual 2026 Nairobi Marathon, a prominent event on Kenya’s sporting calendar. The stretch between the Ole Sereni Interchange and the Lang’ata Road Interchange will be inaccessible to traffic from 6:00 am to 1:00 pm. This six-hour window is deemed essential for ensuring the safety of thousands of participants and the seamless execution of the marathon. The Nairobi Southern Bypass, a vital artery designed to alleviate city congestion, connects Mombasa Road to Ngong Road and serves a substantial daily volume of commuters. Its temporary closure is anticipated to cause considerable disruption, particularly for those travelling to and from Lang’ata, Karen, and the city’s southern districts.

KeNHA Mandates Safety Measures for Marathon

In a public notice, KeNHA explicitly stated that the closure is to "facilitate the 2026 Nairobi Marathon event to take place." The authority underscored the importance of coordinated traffic management during major public gatherings, highlighting the growing prominence of the marathon which draws elite athletes, amateur runners, and fitness enthusiasts from across Kenya and beyond. The decision reflects a common practice in Nairobi, where major sporting and cultural events necessitate traffic flow adjustments. Authorities consistently prioritise participant safety and the overall success of such events, while endeavouring to minimise public inconvenience. The Nairobi Marathon has evolved into more than just a race; it serves as a platform for promoting fitness, tourism, and community engagement, contributing to Nairobi's global reputation in long-distance running.

Alternative Routes and Public Cooperation

To mitigate the expected traffic snarl-ups, KeNHA has provided clear guidance on alternative routes. Motorists intending to access Lang’ata Road are advised to divert onto Mombasa Road (A8) from the Ole Sereni Interchange. From there, they should proceed to the Nyayo National Stadium Roundabout to reach their destination. KeNHA has also issued a call for cooperation from all road users. Traffic police officers and event marshals will be strategically deployed along the affected routes to manage traffic flow and ensure public safety. Motorists are urged to heed their directions and cooperate fully to ensure a smooth experience for both participants and the general public. Drivers are strongly encouraged to plan their journeys well in advance, allocate extra travel time, and remain updated on official traffic advisories to avoid unnecessary delays during the closure period.

The Nairobi Marathon: A Growing Spectacle

The Nairobi Marathon is an annual event that has grown significantly in scale and importance. It typically features multiple race categories, including a full marathon, half-marathon, 10-kilometre, and 5-kilometre races, attracting thousands of participants each year. Beyond its competitive aspect, the event often serves charitable purposes and contributes to the city’s profile as a hub for world-class athletes. The utilisation of major city routes, including sections of the Nairobi Expressway in past editions, underscores its logistical complexity and the need for meticulous planning. This year's closure of a significant portion of the Southern Bypass highlights the event's scale and the authorities' commitment to its successful and safe execution, even at the cost of temporary disruption to daily commutes.

The bottom line

• The Nairobi Southern Bypass will be closed between Ole Sereni and Lang’ata Road interchanges on May 10, 2026, from 6 am to 1 pm.
• The closure is specifically to facilitate the 2026 Nairobi Marathon.
• Motorists are directed to use Mombasa Road (A8) and Nyayo National Stadium Roundabout as an alternative to reach Lang’ata Road.
• The Kenya National Highways Authority (KeNHA) has issued advisories and requested public cooperation.
• The event is a significant annual fixture, drawing numerous participants and requiring traffic management measures.
• Drivers are advised to plan ahead and allow for extra travel time due to the expected disruptions.