Meininger, who grew up in Germany but now lives in London, likes making things. So when he saw how much his young sons enjoyed the jungle gym and play forts at the local park, he made an indoor treehouse for them.
Photovoltaic (PV) solar energy represents a modular technology that can be manufactured in large-scale facilities, generating economies of scale, while also being adaptable to small-scale applications. From residential rooftop systems to large-scale power generation installations, photovoltaic solar energy has established itself as a cost-effective option for electricity production in many countries around the world.
In the nineteenth century, entire railway networks became obsolete almost overnight, not due to physical deterioration, but because of changes in the technical standards that supported them. The expansion of railroads across Europe and North America adopted different track gauges, and as a dominant standard gradually emerged, these infrastructures became incompatible with one another.
Researchers at the Norwegian University of Science and Technology and the University of Tokyo have made a prototype of botanical cement made of desert sand and plant-based additives in hopes that it can be used to build houses and roads. Once mixed, the team adds tiny pieces of wood together and presses them all with heat to produce the cement.
Rather than representing a simple return to the past, this renewed interest reflects a broader reconsideration of how architecture engages with materials, local resources, and environmental conditions.
A Gothic cathedral can take centuries to complete. A world exposition pavilion may stand for six months. A ritual structure in Kolkata rises and vanishes within five days. Yet each draws pilgrimage, shapes collective memory, and reorganizes urban life. If heritage has long been defined by what endures, architecture repeatedly shows that cultural authority can also belong to what gathers people.
Beneath the visible surface of cities lies an invisible architecture. Subways, tunnels, water systems, data cables, and bunkers form a dense network that sustains urban life while remaining largely unseen. The ground beneath our feet is not a void but a complex territory that holds the infrastructures, memories, and anxieties of our age. In recent years, as land becomes scarce and climate pressures intensify, architects and urbanists have turned their gaze downward, rediscovering the subterranean as both a physical and conceptual frontier.
