Meet the leaders transforming our cities

Jonny Anstead is the co-founding partner of TOWN, the largest co-housing builder in the UK. 

TOWN is the developer of Marmalade Lane, a recently built project in Cambridge, UK. The designers Mole Architects, describe the whole site as “essentially a collective playground for kids,” and is recognized as a best-practice model of a co-housing development that maximizes opportunities for free unstructured play for children and an ease of community support for parents.

Anstead will share what drives TOWN’s ethos as a housing developer to “do things differently,”focusing on co-housing, they help ownership collectives through the process of designing together, as well as experimenting with innovating methods of finance in order to bring down costs so that these models of housing are accessible to lower-income residents.

Sam Balto is a passionate Physical Education teacher with over a decade of experience across Washington, DC, Boston, and Portland. Throughout his career, he has been a tireless advocate for active transportation among students. After successfully leading walking school buses for six years, Sam launched a bike bus initiative at Alameda Elementary in 2022 – a program that captured international attention and was even recognized by the White House. Today, Sam is expanding his vision through Bike Bus World, a movement dedicated to inspiring and supporting communities in creating their own bike buses, transforming school commutes into healthier, safer, and more joyful experiences for children everywhere.

Dinah Bornat’s book All to Play For: How to Design Child-Friendly Housing (RIBA Publishers, 2025) is both a plea and a guide—addressed to the UK government in the face of the 1.5 million homes they are promising to deliver – to work with evidence and specifically, consider the needs of children in doing so. Bornat’s research, advocacy, and design practice folds children’s and young people’s views and experiences into the function of their homes and the spaces around them. Her research reveals how our understanding of what makes “good housing” never bothers to observe children’s behavior, let alone speak with them.

At Start with Children Dinah will share multi-house and neighborhood layouts she has studied alongside people living there that prioritize children’s need for doorstep play and places to safely roam, as well as parent’s need for community, and what developers and councils need to know about their benefits for the health of cities.

Jakob Steen Christensen is a partner and co-founder of JAJA Architects. He and JAJA are behind numerous internationally recognized urban facilities such as Konditaget Lüders, Harboøre Activity Hall, and Streetmekka Aalborg. Driven by a core belief in fostering play and movement, JAJA is dedicated to creating climate-responsible cities, buildings, and urban spaces that inspire active and engaging lifestyles. 

Their playful approach emphasizes creating architecture that appeals to children. A notable example is GAME Streetmekka Aalborg, transforming a 1963 production building into a vibrant sports and culture center – now a very popular attraction in Aalborg, Denmark.

Renowned architecture critic and author Adam Gebrian moved with his family to Barcelona in 2017, where his partner would work on her PhD, and he would explore the city’s design heritage each day with their two-year old son. But standing across from legend Antonio Gaudi’s first work – a street lamp from 1879 in Plaça Real – his child’s fascination was instead a large rain puddle just beneath it. “That’s when everything changed.” 

That lesson inspired Three Months in Barcelona, a book that is part architectural guidebook, part memoir, in which Gebrian recounts learning to see the city from the eyes of a toddler and what it reveals about everything from cities’ maintenance and logistics systems, to broad, universal values in master works of architecture. 

The recipient of the prestigious Czech “Architect of the Year” award in 2015, Adam has since written similar accounts in Two Months in Lisbon, Summer in Tenerife, Seven Months in Raleigh, New York, Chicago, and is currently developing a next book on Costa Rica. 

Tim Gill is an independent scholar, writer, and consultant based in London and a global advocate for children’s outdoor play and mobility. He is the author of Urban Playground: How Child-Friendly Planning and Design Can Save Cities (RIBA Publications) and No Fear: Growing Up in a Risk-Averse Society (described in the New York Times as “a handbook for the movement for freer, riskier play”). Tim is a UK Design Council Ambassador. His consultancy clients include corporates, public bodies, and NGOs from throughout the UK and around the world, and he has spoken to audiences in over 25 countries across six continents. A former director of the Children’s Play Council (now Play England), he was seconded to the UK civil service to lead a government review into children’s play in 2003. Tim is a Churchill Fellow who has studied child-friendly urban planning in North and South America, the Middle East, and Europe. He holds degrees in philosophy and psychology from Oxford and London Universities, and an honorary doctorate in education from Edge Hill University. He is also an honorary patron of the UK Forest School Association. Tim writes for the mainstream media, trade, and academic publishing, and appears regularly on radio and television.

In 1991, Eva Kail curated an exhibition of photography that depicted the everyday travel patterns of eight girls and women in Vienna, revealing a perspective of urban space that had never been considered in the city’s urban planning policy, and sparked a conversation that thirty years later has fundamentally transformed how the city sees its own purpose. Two years later Kail led the newly formed “Office of Women” in city hall, which immediately began producing groundbreaking research, including showing how women’s mobility patterns tended to be long sequences of many short stops that ended up exorbitantly expensive compared to the typical male work commuter, and led to a restructuring of transit fares. “Trip chaining” has become a fundamental concept in child-friendly planning today.

For the Conference topic most relevant is the Concept of Gender sensitive parks and playground design, which Vienna implements consequently, based on an eye opening,social science research, 6 model projects and their evaluation and general detailed planning recommendations. Nowadays every new or redesigned public park or playground follows these promising planning principles. Insights like these fed into Vienna’s gender mainstreaming policy which, under Kail’s leadership, has become a globally renowned model, inspiring replicas at the UN, and cities across Europe. In Vienna it has influenced 60 development projects to date, the most recent of which is Europe’s largest new district, Aspern Seestadt, which will eventually house 20,000 people in an area of 240 hectares.

Retired in 2024, Kail will share some reflections on her illustrious career which is still only barely coming into focus for how deeply influential it has been, and will certainly continue to be over the next century of city making.

Petra Marko is an acclaimed architect and placemaking expert dedicated to creating people-centric cities and public spaces. She serves as CEO of the Metropolitan Institute of Bratislava, driving strategic architecture, urban planning, and participatory placemaking initiatives to enhance quality of life. Prior to her role at MIB Petra co-founded and led a London-based placemaking practice active across public spaces design, town centres regeneration and masterplanning in the UK and Cenral Europe. She led the research and campaign for unlocking London’s small sites, sat on UK’s National Infrastructure Commission and taught as design tutor at The London School of Architecture. An advocate for greener cities and active commuting, Petra has co-authored VeloCity, a strategic vision for the future of the countryside; and Meanwhile City, a best practice and how-to guide for temporary interventions. After two decades abroad, she returned to Bratislava to effect positive change.

“It is of utmost importance that the urban child has daily access to nature.” 

Helle Nebelong carries the torch of the outdoor adventure play tradition that originated in Denmark in 1943 before spreading across Europe after the second world war. Across a thirty-year career, she is the designer of Copenhagen’s most popular playground, Valbyparken—widely considered to be one of the best playgrounds in the world, which regularly hosts visiting groups of experts who come to observe it. Helle’s philosophy puts children’s ideas at the center of the design process, giving space for the surprise of children’s creativity to influence major decisions in the layouts, not “what we want for them.” Her playgrounds are places of discovery that encourage the thrill of new risks and she was a pioneer of using what is found on and near the site, and re-using simple materials that are nearby. 

Her most recent project is the largest natural playground in the United States, a 16-acre park adjacent to Colene Hoose Elementary School outside Chicago, Illinois. The project includes 4-acres of restored prairie children can run through, and features 92 different types of trees, 100 different types of shrubs and grasses, and is the most significant planting of indigenous species in the state of Illinois in the past 25 years. 

To bring children to nature also means creating new opportunities for nature itself. 

Matúš Vallo has been the mayor of the capital city of Slovakia, Bratislava, since December 2018, when he won the municipal elections. He successfully defended his mandate in the following 2022 elections. His goal, which he has been fulfilling since taking office, is to make Bratislava a stronger, more resilient, greener, and more transparent city, with quality public spaces, accessible public transportation, and support for disadvantaged groups, together with his team. For his efforts to transform Bratislava into a greener city with quality public spaces, he received the World Mayor Future Award. He is a recipient of the Fulbright Scholarship at Columbia University in New York, as well as scholarships from Bloomberg Philanthropies and Harvard University, which are exclusively offered to only forty mayors worldwide. He is also a co-founder of the Pact of Free Cities, which he established with the mayors of Warsaw, Prague, and Budapest in 2019.