This site is written using HTML 4.01 Strict and CSS and should validate. Any browser that implements the standards correctly should display the site just fine. I don't believe in jumping through hoops to work around browser bugs however I accept just how common Internet Explorer is and the site does experience some of the 'peek-a-boo' bugs that were found in version 6 and remained to some extent in version 7. I am able to control these by some simple but redundant code so I choose to do so.
The site calls on Google Maps to display mapping inline on some pages and this requires use of ECMAScript (JavaScript). If you choose to browse with scripting disabled you aren't going to see the maps. I may choose to use scripting for other purposes but if I do it is unlikely you would miss out on anything important if you disable it. If you would then I will let you know.
The 'polylines' facility in Google Maps uses VML with Internet Explorer. This requires the import of an XML namespace. Google would have it that you need to use XHTML do this but you can just add it to an HTML page and it will work as it is all just 'tag soup' anyway. The page will no longer be valid HTML, of course, but that seems a small price to pay. So if I use 'polylines' on any maps there will be pages that do not validate.
The site is designed around photos so if you are using a text based browser or browse with images disabled you are going to miss out somewhat. I will try to put in 'alt' text on images but I can't promise they'll be truly useful and it is quite possible some will be blank if I have been lazy. Some will say that the 'alt' text is a transparent replacement for the image and that the text should read just like you had a text only page. I think that is not only impractical but it is an incorrect interpretation of the intent of the 'alt' text. I consider that the 'alt' text is there to give an indication of what the image shows and that you should still be aware that it is replacing an image. For that reason I choose to use brackets around my 'alt' text to draw attention to it.
I could do fancy dynamic menus if I wanted to but I would say the majority I see on the net are too easily triggered by accident and are intrusive. Worse still they are often the sole way of navigating the site usefully which isn't much use if they use scripting and you don't.
I am using a sans-serif typeface for most text on this site (typically 'Arial' or 'Helvetica'). That is a cosmetic decision I have made but I do recognise that strictly speaking it ought to be the viewer's choice. However I do leave the default font size well alone. This text is sized at whatever default you have selected on your browser.
I test the site using the latest versions of Internet Explorer and Mozilla Firefox that are available to me. I do not keep old versions of browsers around. It really shouldn't make any difference as all browsers should get it right.
One last point, if anyone wonders why I don't use XHTML when you do seem to see it everywhere then I recommend they read http://www.webdevout.net/articles/beware-of-xhtml.