How to use image tag nested under a href in rails

Question

I'm new to rails and trying to implement a lightbox in rails 4. My question is that how can I write the following code in erb?

<a href="#img1">
  <img src="some_img.jpg">
</a>

<a href="#_" class="lightbox" id="img1">
  <img src="some_img.jpg">
</a>

Answer 1

<%= link_to image_tag("some_img.jpg"), "#img1" %>

<%= link_to image_tag("some_img.jpg"), "#_", :class => "lightbox", :id => "img1" %>

Answer 2

%a#img1.lightbox{:href => "#_"}

  %img{:src => "some_img.jpg"}