Overview
I looked into how to use Rekichizu (historical maps) with Next.js, so here are my notes.
Background
In the following article, I introduced how to use “Rekichizu.”
Then, I learned that the “nationwide version was released” on April 4, 2025.
So I investigated how to integrate it into an application built with Next.js.
Demo App
I prototyped the following application.
https://rekichizu-next.vercel.app/ja/

For the investigation, I aimed to reproduce features such as map switching, overlay, and search functionality provided on the official site. For this implementation, I used the following React library.
https://visgl.github.io/react-maplibre/
Development Notes
Search Feature
For the search feature, I used the GeoLOD API. Note that the official “Rekichizu” site appears to use a dedicated search API.
https://geolod.ex.nii.ac.jp/doc/api/
react-maplibre
I was able to achieve most of what I wanted using this library. However, there were some difficulties, such as it being hard to change the pitch along with terrain ON/OFF using TerrainControl, and addLayer/removeLayer being difficult with useMap.
Summary
I hope this serves as a useful reference for application development using “Rekichizu” and Next.js.
I deeply appreciate those involved in the development of “Rekichizu.”