I don’t think the number of photos is relevant ( 400k is peanuts, frankly ).

Just loading the home page, at 07:50 on a weekday, took 34 seconds, without accessing the actual image gallery; just seven small static thumbnails on a basic HTML page. Edit: that’s on an 80 Mbps connection.

The metric we use at work is that each one-second delay in page loading costs 10% of visitors to abandon. By 20 seconds, we’d be out of business.

Do let me know if you’d like any profiling assistance.

400K is a pretty large number for a website. Its definitely not peanuts. even for a huge corporate entity, let alone an organisation run by volunteers. And yes when there are enough visitors on the rest of the website, even if your home page has nothing but text in it, it can get slow.